WO1995003562A1

WO1995003562A1 - Microelectromechanical television scanning device and method for making the same

Info

Publication number: WO1995003562A1
Application number: PCT/US1994/008165
Authority: WO
Inventors: Michael D. Johnson
Original assignee: Medcam, Inc.
Priority date: 1993-07-19
Filing date: 1994-07-19
Publication date: 1995-02-02
Also published as: SG89230A1; US5920417A; US5673139A; EP0711422A1; US5920417C1; KR960704250A; JPH09502580A; EP0711422A4; AU7400894A; CN1127554A; CA2166605A1; AU689790B2; CN1056452C

Abstract

An electrically actuated microelectromechanical television scanning device for television image scanning or related functions. The scanning device can be produced in forms having characteristic dimensions in the submillimeter range. The scanning device consists of an electrostatically actuated plate (30) with two degrees of freedom. A collimated radiation emitter, collimated radiation detector (52) or other suitable device may be located on the plate or reflected off the plate, facilitating operation of the device as a flying spot scanner, television image dissector or television display. The scanning device can be fabricated similarly to monolithic integrated circuits.

Description

MICROELECTROMECHANICAL TELEVISION SCANNING DEVICE AND METHOD FOR MAKING THE SAME

1. Field of the Invention This invention relates generally to mechanical television scanning mechanisms and more particularly to microelectromechanical television scanning mechanisms fabricated according to the principles used to fabricate monolithic integrated circuits, thus enabling the physical dimensions of the scanning mechanism to be submillimeter in scale.

2. Description of the Prior Art

Typically, prior art mechanical television scanning mechanisms are large, require external light sources or sensors, have limited operating frequencies and geometrical fields of view, and are fragile. Additionally, prior art mechanical scanners generally include many components. Such mechanisms generally require extensive and intricate manufacturing processes, with associated high costs and low reliability.

Therefore, there is a need for a scanning mechanism that is small in size, facilitates integral or other non-integral radiation sources or sensors, has a wide geometrical field of view, high operating frequency and is robust in construction. Of the known mechanical television scanning mechanisms, only the scanner provided by the present invention is fabricated in much the same manner as monolithic integrated circuits, thus enabling the physical dimensions of the device to be exceedingly small.

GOTO, in U.S. Pat. No. 5,097,354, discloses a beam scanner which is an electrostatically actuated, torsionally supported two-dimensional scanning mirror. This scanner is constructed in two components. In addition to its simplicity, the scanner features a torsional mirror mount which limits the range of angular deflection of the mirror. This patent also discloses transducers including a vibrating photoelectric sensor in the focal plane of a Fresnel lens. PETERSEN, in an article entitled "Silicon Torsional Scanning

Mirror", IBM J. Res. Develop., Vol. 24, no. 5, September 1980, discloses a silicon torsional scanning mirror which is electrostatically actuated and torsionally supported on a single scanning axis. The device disclosed is constructed in two components, including a scanning mirror element. The scanning mirror element is fabricated from single crystal silicon, which limits the precision of fabrication due to crystal plane etching.

LIDDIARD, in U.S. Pat. No. 4,708,420, discloses a focal plane scanning device which uses piezoelectric actuators and a mirror rigidly fixed to a central compliant flexure member. This arrangement permits deflection about two axes.

BURKE, in U.S. Pat. No. 4,230,393, discloses a two-axis optical scanner which uses a compliant flexure member. The flexure member is compliant in two axes, with each axis having an associated resonance. The flexure member is excited into oscillation at one end by a mechanical oscillator, and has a scanning mirror located at its other end. The scanning mirror scans in the two axes at the associated resonance frequencies in response to excitation by the mechanical oscillator. LAKERVELD et al., in U.S. Pat. No. 4,073,567, disclose a pivoting mirror device which is actuated electromagnetically. The device includes an oscillating mirror that is centrally supported by a single point bearing, and the bearing permits the mirror to oscillate about two axes. Finally, BAKER et. al., in U.S. Pat. No. 3,471,641, disclose a resonant scanning apparatus for deflecting a mirror which uses electromagnetic or piezoelectric actuators. This device includes a mirror rigidly fixed to a central compliant flexure member that is actuated by the actuators to permit deflection about two axes.

SUMMARY OF THE INVENTION

The long-standing but heretofore unfulfilled need for a scanning device having the desirable features of small physical dimensions, integral light or other radiation sources or sensors, a wide geometrical field of view, high operating frequency, robust construction, easy manufacture, low cost and high reliability, is fulfilled by the invention disclosed and described in the detailed description which follows. According to one aspect, the invention is a scanning device. The scanning device comprises a substrate made from a first material and a flexible joint located above the substrate. The flexible joint is made from a second material. The scanning device further comprises a support attached to the flexible joint. The support is made from a third material. In addition, the scanning device includes an actuator formed on at least one of the substrate, the flexible joint and the support. The actuator is able to cause the support to move relative to the substrate. Further, the scanning device includes an optical element or other energy processing element, such as an optical collimator, on the upper surface of the support. The materials mentioned previously may be the same or any combination of materials required for effective operation of the device.

In one embodiment, the scanning assembly is composed of a

90 cross- (or other) shaped thin film plate of electrically conductive material (e.g., boron-doped polysilicon crystal).

This plate is supported, generally centrally over a substrate, by a flexible member made from a material that is similar to the material from which the plate is made. The flexible member

95 terminates at a fixed base, generally on the substrate, which contains four (or any other desired appropriate number) of electrostatic actuator electrodes. This flexible member extends perpendicularly from the center of the cross- (or other) shaped central plate and is of suitable length to permit sufficient

100 angular displacement of the cross- (or other) shaped central plate.

The four (or other desired number) electrostatic electrodes (e.g., of deposited aluminum film) are located on the fixed base, directly below the four arms of the cross- (or other) shaped 105 central plate, and act as electrostatic actuators of the cross- tor other) shaped central plate. Each conductive electrode has slightly smaller dimensions than the corresponding arm of (or is equal in size to) the cross- (or other) shaped central plate. Electrically conductive lines (e.g., made from deposited aluminum 110 film) or junction isolated conductors from the conductive electrodes communicate with pads located on the fixed base. An insulating film (e.g., of silicon dioxide, or, preferably, of silicon nitride is deposited between the conductive plates, the conductive lines and the fixed base. Attraction and repulsion 115 forces are induced between the base and the cross- (or other) shaped central plate when a voltage is applied between the conductive plates and the arms of the moving cross- (or other) shaped central plate. These forces can cause the cross- (or other) shaped central plate to move in directions about two 120 distinct axes. The previously mentioned flexible member contains any number of electrically conductive lines (e.g., made from deposited aluminum film) or junction isolated conductors deposited on its outer surface. These lines communicate between any desired number of light or other radiation sources or sensors 125 located on the top side of the cross- (or other) shaped central plate and the pads located on the fixed base.

A flexible member perpendicular to the fixed base is not the only way to support the moving cross- (or other) shaped central plate. In another embodiment of the invention, suspension of the

130 cross- (or other) shaped central plate is accomplished by a thin film gimbal. In this embodiment a thin planar film of flexible material (e.g., polycrystalline silicon) is supported above the fixed base and perforated in such a manner as to form a gimbal ring supported externally by two thin, torsionally flexible

135 collinear supports. In addition, the cross- (or other) shaped central plate is formed centrally by the perforations. The cross- (or other) shaped central plate is supported by two further thin, torsionally flexible, collinear supports that are positioned orthogonally to the aforementioned two collinear

140 supports. In this manner the central plate is free to be rotated out of the plane of the thin film of flexible material in any desired direction. The cross- (or other) shaped central plate has any desired number of light or other radiation sources or sensors formed on its upper surface, with conductive lines

145 communicating from the light or other radiation sources or sensors to stationary electrodes located on the fixed base. The entire gimbal assembly is suspended above the fixed base, which contains the electrostatic actuator plates.

A further means of suspension of the moving cross- (or

150 other) shaped central plate is by thin film spiral springs. In a preferred embodiment of the invention involving this method, a thin film of flexible material (e.g., polycrystalline silicon) is supported above the fixed base and perforated in such a manner as to form a series of spirals (smooth or rectilinearly

155 discontinuous) communicating from the internal edge of a circular (or rectangular) perforation to the outer edge of the cross- (or other) shaped central plate. In this manner the central plate is free to be rotated out of the plane of the thin film of flexible material in any desired direction. The cross- (or

160 other) shaped central plate has any desired number of light or other radiation sources or sensors formed on its upper surface, with conductive lines communicating from the light or other radiation sources or sensors to stationary electrodes located on the fixed base. The entire spring assembly is suspended above

165 the fixed base, which contains the electrostatic actuator plates. The electrostatic actuators may act in the same manner as in the gimbal plate mentioned above or in the following fashion. The electrostatic actuator base plates are formed of the same shape and are parallel to the spiral springs. When a voltage potential

170 is applied between the base plates and the springs, a continuous force is applied along the entire length of the spring. Since the spring is relatively long, the small force applied over the entire length of the spring induces a relatively large excursion at the point of connection to the central plate. 175 Actuation of any of the embodiments of the inventive device mentioned above is not necessarily electrostatic. One possible additional way of actuating the embodiment is magnetically. To accomplish this, conductors of deposited aluminum film are shaped to form spiralling coils on the arms of the cross- (or other) 180 shaped central plate. When the inventive device is placed in a magnetic field of proper orientation, current passing through any one of the coils produces a moment which deflects the cross- (or other) shaped member in a known direction. A proper combination of the currents through selected coils can cause the cross- (or 185 other) shaped central plate to deflect in the desired fashion. While operating under the control of magnetic fields generated by coils, the inventive device operates similarly to a moving coil galvanometer, which is known in the prior art.

Still another additional way to actuate the cross- (or 190 other) shaped central plate involves piezoelectric actuators. For piezoelectric action, four small blocks of conventional piezoelectric crystal film (e.g., zinc oxide) are formed, one block directly under each of the arms of the cross- (or other) shaped central plate. The piezoelectric crystal films are 195 individually fixed between the base of the inventive device and the arms of the cross- (or other) shaped central plate. Actuation occurs when current is applied, in the manner known in the prior art, across the piezoelectric crystal films. The piezoelectric crystal films expand or contract in a direction 200 perpendicular to the plane formed by the arms of the cross- (or other) shaped central plate in accordance with the polarity and magnitude of voltage applied. When the motion of the piezoelectric crystal films is properly coordinated, the desired scanning motion of the cross- (or other) shaped central plate is 205 achieved.

Yet another way to actuate the cross-shaped central plate uses forces that are created by thermal stress. By locally heating the member that connects between the base and the cross-shaped central plate (through resistive or optical means), 210 a temperature gradient causes a bending moment in the connecting member. This bending moment causes the connecting member to bend away from the source of heat, much in the same manner as a bimetallic strip bends. By selectively heating different positions on the connecting member, any desired scanning motion 215 of the cross-shaped central plate can be generated.

The transducers located on the top of the cross-shaped central plate and/or on the fixed base can serve a variety of functions regardless of how the cross-shaped central plate is caused to scan. In the case where a laser diode or other 220 coUimated radiation emitter is located on the moving cross-shaped central plate and photoreceptors or other radiation detectors (e.g., phototransistor, photodiode, etc.) are located on the fixed base, the inventive device acts as a flying spot scanner. The laser light or other radiation emitted from the 225 laser diode (or other) coUimated radiation emitter is scanned by the moving cross-shaped central plate across an object in a raster pattern. The light or other radiation reflected from the object is detected by the stationary photoreceptor radiation detector, which converts the variations of the detected reflected 230 light (or other) radiation into a video signal. Additionally, photoreceptors or other radiation detectors can be collocated on the moving cross-shaped central plate with the laser diode or other coUimated radiation emitter, permitting a more compact design.

235 When the diode laser or other coUimated radiation emitter located on the top of the moving cross-shaped central plate is modulated and scanned in accordance with an incoming video signal, it is possible to use the inventive device as a television monitor. The television monitor constructs an image

240 by projecting the modulated coUimated laser light or other radiation beam from the scanner onto a translucent or opaque screen.

If a photoreceptor (or other coUimated radiation detector) replaces the laser diode (or other coUimated radiation emitter)

245 on the moving cross (or other central plate) member, the inventive device can be used as an image dissector. Ambient light (or other radiation) from a self-contained source (such as a laser light emitting diode) can be reflected from the object being imaged and is then detected by the photoreceptor (or other

250 coUimated radiation detector) which is scanned across the directions of the image by the moving cross-shaped central plate. Some form of light or other radiation collimator (e.g., a lens, a gradient index lens or tube made of deposited aluminum) can also be located on the moving cross-shaped central plate above

255 the photoreceptor or other radiation detector, thus providing further directional sensitivity to the photoreceptor or other radiation detector. High directional sensitivity of the photoreceptor or other radiation detector can be required in this mode of operation in order to dissect the image by one beamwidth 260 of the laser light beam per scanner pass.

A further embodiment of the inventive device includes a combination of both a laser diode (or other coUimated radiation emitter) and coUimated photoreceptor (or other radiation detector) on the cross-shaped central plate. This combination

265 of elements permits operation of the inventive device in any of the previously mentioned ways by activation of the laser diode

(or other coUimated radiation emitter) or photoreceptor (or other coUimated radiation detector, or any combination thereof.

Also, if a reflective surface is formed or placed on the top

270 surface of the cross-shaped central plate, a still further embodiment of the inventive device can be used as a reflective flying spot scanning device, with light or other radiation from a stationary light (or other coUimated radiation) source (such as a laser diode) reflecting off the surface of the cross-shaped

275 plate as it moves. The emitted, coUimated radiation beam is scanned across the imaged object and radiation reflected off the object is detected by a stationary radiation detector.

Additionally, if the reflective surface is formed or placed on the top surface of the central plate, a still further 280 embodiment of the inventive device can be used as a reflective television monitor, with radiation from a stationary modulated coUimated radiation source (e.g., a laser diode) reflecting off the surface of the central plate as it moves. The emitted, modulated coUimated radiation beam is scanned across a 285 translucent or opaque screen and viewed by an observer.

Further, if incoming radiation from an object is reflected off the surface of the central plate to a coUimated radiation detector, the device acts as a reflective image dissector.

Other objects of this invention will become apparent in the 290 detailed description of the preferred embodiment of the invention. The invention comprises the features of construction, combinations of elements and arrangements of parts that will be exemplified in the construction hereinafter set forth, and the scope of the invention will be determined by the claims.

295

BRIEF DESCRIPTION OF THE DRAWINGS

Figure la is an orthogonal view of a first preferred embodiment of the microelectromechanical television scanning device according to the invention, the first preferred embodiment

300 having a central plate suspended cross-shaped plate on a flexible member.

Figure la is an electrical schematic of the scanning device illustrated in Figure la.

Figure 2 is a top view of a second preferred embodiment of 305 the scanning device of the invention, the second embodiment having a gimbaled moving plate suspension.

Figure 2a is a top view of the actuator electrodes for the scanning device illustrated in Figure 2.

Figure 2b is an electrical schematic of the scanning device 310 illustrated in Figure 2.

Figure 3 is a top view of a third preferred embodiment of the scanning device of the invention, the third embodiment having an alternate spiral spring moving plate suspension.

Figure 3a is a revision of the third embodiment of the 315 invention.

Figure 4 is an orthogonal view of a fourth preferred embodiment of the scanning device of the invention, the fourth embodiment having a magnetically actuated configuration.

Figure 4a is an electrical schematic of the scanning device 320 illustrated in Figure 4.

Figure 5 is an orthogonal view of a fifth preferred embodiment of the scanning device of the invention, the fifth embodiment having a piezoelectrically actuated configuration.

Figure 5a is an electrical schematic of the scanning device 325 illustrated in Figure 5.

Figure 6 is an orthogonal view of a sixth preferred embodiment of the scanning device of the invention, the sixth embodiment having a thermally actuated configuration.

Figure 6a is an electrical schematic of the scanning device 330 illustrated in Figure 6.

Figure 7a illustrates a high amplitude action of the moving plate about a single axis.

Figure 7b illustrates a low amplitude action of the moving plate about a single axis. 335 Figure 7c illustrates a high amplitude action of the moving plate on a gimbal mount.

Figure 7d illustrates a low amplitude action of the moving plate on a gimbal mount.

Figure 8 is a detailed view of the electrical communication 340 between a photoelectric device and a conductive line on a preferred embodiment of the invention.

Figure 9 is a detailed view of a scanning radiation emitter configuration in accordance with the present invention.

Figure 10 is a detailed view of an optically coUimated 345 radiation detector configuration in accordance with the present invention.

Figure 11 is a detailed view of a tube-collimated radiation detector configuration in accordance with the present invention. Figure 11a is a detailed view of a combination laser and 350 gradient index lens coUimated photoreceptor or detector for other radiation in accordance with the present invention.

Figure 12 is a detailed view of a gradient index lens coUimated radiation detector configuration in accordance with the present invention. 355 Figure 13 is a detailed view of a coUimated radiation emitter and coUimated radiation detector configuration in accordance with the present invention.

Figure 14 is an orthogonal view of a seventh preferred embodiment of the scanning device of the invention, the seventh 360 embodiment having a reflective central plate.

Figure 14a is an electrical schematic of the scanning device illustrated in Figure 14a.

Figure 15 illustrates the action of an embodiment of the present invention in use as a television monitor. 365 Figure 16 illustrates the action of an embodiment of the present invention in use as an image dissector.

Figure 16a is an orthogonal view of the scanner 158. 370 Figure 17 illustrates the action of an embodiment of the present invention in use as a reflective flying spot scanner.

Figure 18 illustrates the action of an embodiment of the present invention in use as a reflective image dissector.

Figures 19a and 19b are a flow chart of an exemplary process 375 for producing the illustrated embodiments of the present invention.

Figure 20 is a first mask for use with the flow chart of Figures 19a and 19b.

Figure 21 is a second mask for use with the flow chart of 380 Figures 19a and 19b.

Figure 22 is a third mask for use with the flow chart of Figures 19a and 19b.

Figure 23 is a fourth mask for use with the flow chart of Figures 19a and 19b. 385 Figure 24 is a fifth mask for use with the flow chart of Figures 19a and 19b.

Figure 25 is a sixth mask for use with the flow chart of Figures 19a and 19b.

Figure 26 is a side view of a preferred embodiment of the 390 invention.

Figure 27a is a top view of a glass wafer of the invention. Figure 27b is a top view of a thin film of the invention. Figure 28 is a side view of a configuration of the invention. 395 Figure 29 is a top view of a thin film of the invention. Figures 30a-d are a flow chart of an exemplary process for producing the another illustrated embodiment of the present invention.

Figure 31 is a first mask for use with the flow chart of 400 Figures 30a-d.

Figure 32 is a second mask for use with the flow chart of Figures 30a-d.

Figure 33 is a third mask for use with the flow chart of Figures 30a-d. 405 Figure 34 is a fourth mask for use with the flow chart of Figures 30a-d. Figure 35 is a fifth mask for use with the flow chart of Figures 30a-d.

Figure 36 is a sixth mask for use with the flow chart of 410 Figures 30a-d.

Figure 37 is a seventh mask for use with the flow chart of Figures 30a-d.

Figure 38 is a eighth mask for use with the flow chart of Figures 30a-d. 415 Figure 39 is a ninth mask for use with the flow chart of Figures 30a-d.

Figures 40a and 40b are views of the fabricated device from the flow chart of Figures 30a-d.

Figure 41 is a top view of an array of individual copies 420 of the scanning device of the present invention.

Figure 41a is a close-up view of a portion of the array shown in Figure 40.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

425 Figure 1 is an orthogonal view of a first preferred embodiment of the microelectromechanical television scanning device according to the invention, the first preferred embodiment having a suspended cross- (or other) shaped central plate. The scanning cross-shaped central plate 30 (e.g., made from a

430 material such as deposited n-doped polysilicon) is affixed to a flexible shaft 32 preferably made from the same material as, and in electrical communication with, the scanning cross-shaped central plate 30. The flexible shaft 32 is anchored to a fixed base 34, preferably made of the same material as, and in

435 electrical communication with, the flexible shaft 32. The scanning cross-shaped central plate 30 has arms denoted by reference numerals 36, 38, 40 and 42. The fixed base 34 has electrodes 44, 46, 48 and 50 (e.g., made of deposited aluminum film) formed thereon. The electrodes 44, 46, 48 and 50

440 respectively attract or repel the moving cross arms 36, 38, 40 and 42, depending upon the voltage applied to them. A photoelectric device 52 (e.g., a laser diode (or other coUimated radiation emitter) or coUimated photoreceptor (or other radiation detector) is located on the top of the scanning

445 cross-shaped central plate 30. Electrical communication with the photoelectric device 52 is accomplished through a conductive line 54' (e.g., made of deposited aluminum film) and an electrode 54 preferably made from the same material as the conductive line 54 ' . Another photoreceptor radiation detector or photoemitter

450 56 may be located on the fixed base 34, with electrical communication established by a conducting line 57 (or junction isolated conductor, e.g., made of deposited aluminum film and an electrode 58 made from the same material or junction isolated conductor) .

455 Figure la is an electrical schematic of the scanning device illustrated in Figure 1. Each schematic symbol represents the corresponding element with the same number as in Figure 1. Feedback controlled oscillators 65 drive the electrostatic actuator pairs 36 and 44, 38 and 46, 40 and 48, and 42 and 50.

460 A common ground 67 completes the device circuit. Devices 52 and 56 are either radiation emitters or radiation detectors.

Figures 2 and 2a are top views of a second preferred embodiment of the scanning device of the invention, the second embodiment having a gimbaled moving plate suspension. A thin 465 film 60 of a flexible material (e.g., deposited n-doped polysilicon) is located above the fixed base 34, with the electrodes 44, 46, 48 and 50 being formed on the fixed base 34.

The thin film 60 is perforated by perforations 62 in a manner that forms small torsionally flexible regions 64. Additionally,

470 a gimbal ring 66 and a central gimbal plate 68 is formed by the perforations 62. The gimbal ring 66 is free to rotate about the x-axis 66', and the central gimbal plate 68 is free to rotate about the y-axis 68'. Electrical communication between the outside electrode 54 and the photoelectric device 52 is

475 established by the conducting line 54'. Through holes 63 are cut in the thin film 60 to provide access to electrodes 44, 46, 48 and 50. The features shown in Figure 2 are suspended above the items in Figure 2a with sufficient spacing between them to permit free out-of-plane rotation of the gimbal ring 66 and the central

480 plate 68. As with the device illustrated in Figure 1, a stationary radiation detector 56 may be located on the flexible film 60 with an associated electrode 58.

Other alternative forms of gimballing mechanisms are also possible. In particular, it is possible to form a gimbal device 485 having hemispheric cylindrical bearings which are formed to create low-friction rolling-contact with a base plate. Such alternative forms of gimballing bearing mechanisms or other mechanisms which allow a plate such as plate 60 to freely respond to forces such as those produced by the electromagnetic and other 490 mechanisms described herein, are considered to be encompassed by the present patent specification.

Figure 2b is an electrical schematic of the scanning device illustrated in Figures 2 and 2a. Each schematic symbol represents the corresponding element with the same number as in Figures 2 and 2a. Feedback controlled oscillators 65 drive the electrostatic actuator pairs 36 and 44, 38 and 46, 40 and 48, and 42 and 50. A common ground 67 completes the device circuit. Devices 52 and 56 are either radiation emitters or radiation detectors. Figure 3 is a top view of a third preferred embodiment of the scanning device of the invention, the third embodiment having an alternate spiral spring moving plate suspension, and Figure 3a is a revision of the third embodiment. The thin film 60 of the flexible material is located above the fixed base 34, with the electrodes 44, 46, 48 and 50 being formed on the fixed base 34, in the area covered by a central plate 72. The thin film 60 is perforated by the perforations 62 in a manner that forms long, thin linear springs 70. Additionally, the modified scanning cross-shaped central plate 72 is formed by perforations 62. The scanning cross-shaped central plate 72 is free to rotate about the x- or y-axis 68' and 64', respectively). Electrical communication between the electrode 54 and the photoelectric device 52 is established by the conducting line 54 ' . When a voltage potential is applied between the lower electrodes 44, 46, 48 and 50 and springs 70, a continuous force is applied along the entire length of the spiral springs 70. Since each spiral spring 70 is relatively long, the small force applied along the entire length of the spring 70 induces a relatively large excursion at the point of connection to the plate 72. Figure 4 is an orthogonal view of a fourth preferred embodiment of the scanning device of the invention, the fourth embodiment having a magnetically actuated configuration. The scanning cross-shaped central plate 30 includes a set of electrically conductive coils 74 and 76 (e.g., made of deposited 525 aluminum film) formed on its upper surface. Electrodes 78 and 80 electrically communicate with the coils 74 and 76, respectively, through electrically conductive traces. When the scanning cross-shaped central plate 30 is positioned in a magnetic field 82 and electric current is modulated in the proper 530 fashion in the coils 74 and 76, the scanning cross-shaped central plate 30 will scan in any desired motion.

Figure 4a is an electrical schematic of the scanning device illustrated in Figure 4. Each schematic symbol represents the corresponding element with the same number as in Figure 4. 535 Feedback controlled oscillators 65 drive the moving magnetic coils 74 and 76. A common ground 67 completes the device circuit. Device 52 is either a radiation emitter or radiation detector.

Figure 5 is an orthogonal view of a fifth preferred

540 embodiment of the scanning device of the invention, the fifth embodiment having a piezoelectrically actuated configuration.

The piezoelectric crystals 84, 86, 88 and 90 (e.g., made of deposited zinc oxide film) are formed on the fixed base 34, and support the scanning cross-shaped central plate 30. Electrical

545 communication is established between the electrodes 92, 94, 96 and 98 (e.g., made of deposited aluminum film), through the piezoelectric crystals 84, 86, 88 and 90, respectively, to the moving cross arms 36, 38, 40 and 42, respectively, and down through the flexible shaft 32. The electrodes 92, 94, 96 and 98

550 are electrically isolated from the fixed base 34.

Figure 5a is an electrical schematic of the scanning device illustrated in Figure 5. Each schematic symbol represents the corresponding element as numbered in Figure 5. Feedback controlled oscillators 65 drive the piezoelectric actuator sets

555 36, 84 and 92; 38, 86 and 94; 40, 88 and 96; and 42, 90, and 98. A common ground 67 completes the device circuit. Device 52 is either a radiation emitter or radiation detector.

Figure 6 is an orthogonal view of a sixth preferred embodiment of the scanning device of the invention, the sixth

560 embodiment having a thermally actuated configuration. The thermal lasers lOOa-d emit corresponding light or other radiation beams 102a-d containing light or other radiation at a suitable wavelength, to heat the flexible shaft 32 at corresponding portions of an area 104. After the area 104 of the flexible

565 shaft 32 is heated by the light or other radiation beam or beams selected from the set of beams 102a-d, the flexible shaft 32 bends away from the direction of the source of the heat, in this case away from the direction of the selected radiation beams 102a-d. By appropriately varying the heating and cooling of the

570 area 104 by means of the lasers lOOa-d, the scanning cross-shaped central plate 30 will scan in the desired direction.

Figure 6a is an electrical schematic of the scanning device illustrated in Figure 6. Each schematic symbol represents the corresponding element as numbered in Figure 6. A common ground

575 67 completes the device circuit. Device 52 is either a radiation emitter or radiation detector.

Two versions of the scanning mechanism are illustrated as represented by Figure 1 and by Figures 2 and 2a. 580 Figure 7a illustrates a high amplitude action of the moving plate, on a flexible shaft 32, about a single axis. The phantom view of the moving cross-shaped central plate 106 illustrates one extreme of excursion (showing the bent flexible shaft 32) , while the solid view of the scanning cross-shaped central plate 30

585 illustrates the other extreme of excursion. The angle of view 108 experienced by the scanning cross-shaped central plate 30 in this situation is wide compared to the field of acceptance 109 that would pertain if the central plate 30 were equipped with a collimator.

590 Figure 7b illustrates a low amplitude action of the moving plate, on a flexible shaft, about a single axis. The phantom view of the scanning cross-shaped central plate 110 illustrates one extreme of excursion, while the solid view of the scanning cross-shaped central plate 30 illustrates the other extreme of

595 excursion. The angle of view 112 experienced by the scanning cross-shaped central plate 30 in this situation is narrow, but is still somewhat large compared to the field of acceptance 113 that would pertain if the central plate 30 were equipped with a collimator.

600 Figure 7c illustrates a high amplitude action of the moving plate, on a gimbal mount supporting the gimbal plate 68. The phantom view of the moving gimbal plate 68 illustrates one extreme of excursion, while the solid view of the scanning gimbal plate 68 illustrates the other extreme of excursion. The angle 605 of view 108 experienced by the scanning cross-shaped central plate 68 in this situation is wide compared to the field of acceptance 109 that would pertain if the central plate 68 were equipped with a collimator.

Figure 7d illustrates a low amplitude action of the moving 610 plate 68, on a gimbal mount, about a single axis. The phantom view of the scanning central gimbal plate 68 illustrates one extreme of excursion, while the solid view of the scanning gimbal plate 68 illustrates the other extreme of excursion. The angle of view 112 experienced by the scanning cross-shaped central 615 plate 68 in this situation is narrow, but is still somewhat large compared to the field of acceptance 113 that would pertain if the gimbal plate 68 were equipped with a collimator.

From Figures 7a-d, it is readily apparent that increasing the amplitudes of the signals input to the actuating components 620 increases the angle of view of the scanner. Thus, the angle of view of the scanner is easily and readily changed at will by changing the signals to the scanning mechanism. This produces the effect of a varying focal length lens (i.e., zoom lens) without the associated complicated optics. Provision must be 625 made, however, to reduce the instantaneous field of view of the collimator when reducing the overall field of view and vice versa.

Figure 8 is a detailed view of the electrical communication between a photoelectric device and a conductive line on a 630 preferred embodiment of the invention. It illustrates the electrical communication between the photoelectric device 52 and electrode 54 through the conductive line 54. An insulative material 114 (e.g., made of deposited silicon oxide (or preferably, silicon nitride film) electrically isolates the 635 conductive line 54' from the scanning cross-shaped central plate 30, the fixed base 34 and flexible shaft 32.

Figure 9 is a detailed view of a scanning laser configuration in accordance with the present invention. The bottom of a stacked diode laser 116 is in electrical 640 communication with the scanning cross-shaped central plate 30 and the flexible shaft 32. A conductive ring 118 electrically communicates with the top layer of the stacked diode laser 116 and the conductive line 54'. The insulative material 114 serves as both a mechanical support for the conductive ring 118 and an 645 electrical insulator for the conductive ring 118 and the conductive line 54'. The stacked diode laser 116 produces a light or other coUimated radiation beam 120.

Figure 10 is a detailed view of an optically coUimated photoreceptor or other radiation detector configuration in 650 accordance with the present invention. A lens 122, made of transparent material (e.g., made of deposited silicon oxide), focuses incoming light or other radiation rays 124 onto a photosensitive semiconductor junction 126 (e.g., made of p-doped silicon). The conductive line 54' and the insulative material 655 114 serve the same function as in Figure 8.

Figure 11 is a detailed view of a tube-collimated photoreceptor or other radiation detector configuration in accordance with the present invention. A tube 128, made of an electrically conductive material (e.g., made of deposited

660 aluminum) , passes an incoming incident light or other radiation ray 130 onto a photosensitive semiconductor junction 126. The tube 128 simultaneously prevents any off-axis light or ray 132 or radiation from reaching the photosensitive semiconductor junction 126. The tube 128 has a field of view defined by angle

665 133. The tube 128 is electrically isolated from the scanning cross-shaped central plate 30 and the flexible shaft 32, but is in electrical communication with the photosensitive semiconductor junction 126 and the conductive line 54'. The conductive line 54' and the insulative material 114 serve the same functions as

670 they serve in Figure 8.

Figure 11a is a detailed view of a combination laser and gradient index lens coUimated photoreceptor or detector for other radiation in accordance with the present invention. The gradient index refractive element 85 is located above the

675 radiation detector 126. The gradient index refractive element 85 performs a similar function to that performed by the lens 122 in Figure 10. Light rays 83 are coUimated and directed to the radiation detector 81. A gradient index refractive element is a very selective collimator which operates with only a relatively

680 small distance between its front surface and the radiation detector 126. Figure 11a is also a side view of the configuration illustrated in Figures 2 and 2a. The electrode base 147 corresponds to 34 in Figure 2a.

Figure 12 is a detailed view of a moving reflector equipped

685 with a combination coUimated radiation emitter and a coUimated radiation detector configuration in accordance with the present invention. The stacked diode laser 116 functions as it does in Figure 9, and the tube-collimated radiation detector 126 functions as in Figure 11. An additional conductive line 91 is

690 required for electrical communication of the photosensitive semiconductor junction 126 with an external electrode.

Figure 13 is a detailed view of a moving reflector configuration in accordance with the present invention. The device is actuated in the same manner as described in Figure 1

695 except that a reflector 136 (e.g., made of deposited aluminum film) is substituted for the photoelectric device 52. Figure 13a is an electrical schematic of the scanning device illustrated in Figure 13. Each schematic symbol represents the corresponding element with the same number as in Figure 13. 700 Feedback controlled oscillators 65 drive the electrostatic actuator pairs 36 and 44, 38 and 46, 40 and 48, and 42 and 50. A common ground 67 completes the device circuit.

Figure 14 illustrates the action of an embodiment of the present invention in use as a flying spot scanner. The scanner

705 138 is in the configuration detailed in Figure 9 with the photoreceptor 56 located on the fixed base 34. A light beam 140 emitted from the stacked diode laser 116 (See Figure 9) is scanned across an object 142 in a motion pattern such as the raster-scan motion indicated by the reference numeral 144. Any

710 light in the light beam 146 that is reflected from the object 142 is detected by the photoreceptor 56 located on the fixed base 34.

Figure 14a is an orthogonal view of the scanner 138. The components are substantially identical to the first preferred embodiment shown in Figure 14, and the corresponding parts have

715 corresponding reference numerals.

Figure 15 illustrates the action of an embodiment of the present invention in use as a television monitor. The scanner 148 is in the configuration detailed in Figure 9. A light beam 140 emitted from the stacked diode laser 116 is scanned across an 720 opaque screen 150 in a motion pattern such as the raster scan motion indicated by the reference numeral 144. Any light in the light beam 152 that is reflected from the opaque screen 150 can be observed by an observer 154 located in front of the opaque screen 150. If the opaque screen 150 is translucent, the image 725 produced on the opaque screen 150 can be observed by an observer 156 located behind the opaque screen 150.

Figure 16 illustrates the action of an embodiment of the present invention in use as an image dissector. A scanner 158 is in the configuration detailed in Figure 10 or Figure 11 with a

730 photoemitter 56 located on the fixed base 34. A beam 152 of ambient light reflected off an image field 164 is detected by the coUimated photoreceptor 126 (See Figures 10 or 11). The coUimated photoreceptor 126 is scanned across the image field 164 in a motion pattern such the raster scan motion indicated by

735 the reference numeral 166. The beam 152 of ambient light is supplied by either an external source 168 or a self contained photoemitter 160 located on the fixed base 34 of the scanner 158.

Figure 16a is an orthogonal view of the scanner 158. The components are substantially identical to the first preferred

740 embodiment shown in Figure 16, and the corresponding parts have corresponding reference numerals.

Figure 17 illustrates the action of an embodiment of the present invention in use as a reflective flying spot scanner. A scanner 170 is in the configuration detailed in Figure 13, with

745 the addition of a photoreceptor 56 located on the fixed base 34. A light beam 140 that is reflected off the object 142 (See Figure 17) is detected by the photoreceptor 56 located on the fixed base 34.

Figure 18 illustrates the action of an embodiment of the

750 present invention in use as a reflective image dissector. The scanner 170 is in the configuration detailed in Figure 13. A beam 162 of ambient light reflected off an object in the image field 164 is detected by a coUimated photoreceptor 174. The coUimated photoreceptor 174 is scanned across the image field 755 164 in the motion indicated by the reference numeral 166. The beam 162 of ambient light that is reflected from the object 99 is detected by the radiation detector 43 located on the fixed base 32.

Figures 19a and 19b are a flow chart of an exemplary process

760 for producing the illustrated embodiments of the present invention. The steps in the exemplary process are generally conventional steps in a conventional process familiar to those skilled in the art of producing microelectronic circuitry. The process begins with a wafer of n-doped silicon material sliced

765 from an appropriately produced boule (step 200). This wafer serves as the base for the microelectromechanical television scanner of the invention. Next, a thin layer of silicon nitride is deposited over the surface of the wafer of n-doped silicon material (step 202) . This produces an insulator between the base

770 and the actuator of the scanner of the present invention. Next a layer of aluminum is deposited over the insulation layer placed in step 202 (step 204). This serves as the material from which the actuator (and specifically, the actuator electrodes 44, 46,

48 and 50) will be formed. Over the surface of the aluminum

775 layer is deposited a layer of photoresist (step 206) which is exposed through the first mask (step 208).

Figure 20 is a first mask for use with the flow chart of Figures 19a and 19b. The first mask causes the photoresist deposited in step 206 of Figure 19a to make the aluminum layer 780 susceptible to etchants which cause the removal of the aluminum layer and the nitride layer in all areas except those which are not exposed through the mask shown in Figure 20. Therefore, the first mask generates four generally arrowhead-shaped areas 180 to be masked while the rest of the nitride and aluminum layers 785 on the upper surface of the fixed base 34 to be made susceptible to etchants.

Returning to the flow chart of Figures 19a and 19b, the portions of the aluminum and silicon nitride layers which have not been protected by the first mask to be respectively etched 790 away, in accordance with conventional processing techniques (steps 210 and 212). Following this, the photoresist deposited in step 206 is stripped from the upper surfaces of the remaining portions of the uppermost aluminum layer (step 214).

Next a thick layer of silicon oxide is formed over the base,

795 silicon nitride and aluminum layers of the wafer (step 216) . The purpose of the layer of silicon oxide deposited in step 216 is to electrically insulate the aluminum layer from the remainder of the transducer, and its thickness is great enough to produce the desired degree of electrical insulation. However, the

800 primary purpose of this layer is to provide a support for further construction of the device. Eventually, this layer will be removed by etching. Next, a second layer of photoresist is formed over the thick layer of oxide, in accordance with the pattern 182 of a second mask (step 218). Figure 21 is a second

805 mask for use with the flow chart of Figures 19a and 19b. It defines the areas over the aluminum electrodes formed previously which are to be electrically insulated and on which polysilicon will be deposited.

Returning to the flow chart of Figure 19a, the photoresist

810 layer deposited in step 218 is exposed through the second mask to define the shape of the insulation (preferably taking the form of a thick layer of silicon dioxide placed over the aluminum electrodes) (step 220). Next, the thick silicon oxide layer is etched from those areas exposed through the second mask (step 815 222), leaving the desired insulation (i.e., the thick silicon oxide patch) . After the insulation patch has been formed, the photoresist deposited in step 218 is stripped away (step 224).

The next stages in the process described in the flow chart of Figures 19a and 19b define the gimbal of the second preferred

820 embodiment of the scanner of the present invention (see Figures

2 and 2a) . A layer of conventional polysilicon is deposited over the insulated (by means of a thick silicon oxide layer placed over) aluminum electrodes (step 226) and a layer of photoresist formed over the upper surface of the layer of polysilicon (step

825 228). The layer of silicon polysilicon is exposed through a third mask (step 230). Figure 22 is a third mask for use with the flow chart of Figures 19a and 19b. The third mask defines the perforations 184 which create the gimbal mechanism, which allows the scanner to move mechanically in response to electrical

830 signals which will be supplied to it. An additional area of polysilicon 186 is etched away which provides future attachment openings for the lower aluminum electrodes. The gimbal shown in

Figure 22 has two pairs of pivot points arranged orthogonally to one another. If desired any other appropriate type of gimbal

835 device, such as the spiral gimbal shown in Figure 3 may be formed at this stage.

As shown in Figure 19a, the polysilicon layer deposited in step 226 is etched in accordance with the pattern produced by exposing the photoresist through the third mask (step 232) and

840 then the photoresist deposited in step 228 is stripped away (step

234) . In the next stage of processing, the photodiodes 126 on the upper surface of the scanner are produced (see Figures 10 and

11). The process begins with the deposit of a layer of

845 photoresist over the entire upper surface of the device at this stage of its production (step 236). The deposited photoresist is then exposed through the fourth mask (step 238). Figure 23 is the fourth mask for use with the flow chart of Figures 19a and

19b. The fourth mask defines two small circles 180 at the center

850 of the scanner, p-type ions are implanted through the two small circles 180 to produce the pn junction of the photodiode 126

(step 240) and the photoresist deposited in step 236 is stripped away (step 242) .

The next stage of processing is to produce the insulated 855 connections between the photodiode 126 formed in steps 236-242 and the external world. First, a thin silicon nitride layer is formed over the upper surface of the scanner as it exists at this stage of the process (step 244). This will serve as the insulator 114 between the interconnections and the remainder of 860 the scanner (see Figures 10 and 11). Next an aluminum layer is deposited over the thin nitride layer formed in step 244 (step 246). After this, a layer of photoresist is deposited (step 248) and the photoresist exposed through a fifth mask (step 250).

Figure 24 is a fifth mask for use with the flow chart of 865 Figures 19a and 19b. The fifth mask produces the electrical traces 190 between the photodiodes 192 formed previously and pads 194. The aluminum layer formed in step 246 is stripped away according to the pattern of the fifth mask (step 252), the nitride layer deposited in step 244 is stripped away (step 254) 870 and the photoresist deposited in step 248 is then stripped away ( step 256 ) .

In the next stage of the process shown in the flow charts of Figures 19a and 19b, the cross-shaped central plate and gimbal ring are formed by undercutting the oxide formed in step 216 to 875 separate the resulting thin layer from the base layer formed by the original wafer of silicon material. This is accomplished by depositing a layer of a photoresist (step 258) and exposing the photoresist through a sixth mask (step 260). Figure 25 is an example of the sixth mask for use with the flow chart of Figures 880 19a and 19.

In accordance with the pattern 196 of photoresist deposited in step 258 and exposed in step 260, the thick oxide layer is etched away using a fast etchant (step 262). This causes the oxide under the photodiodes to be etched away, leaving only a 885 thin layer of elevated polysilicon having the photodiodes formed thereon.

Now that the exemplary embodiment of the scanner of the present invention has been formed on the upper surface of the base material of n-doped wafer, it is separated from the

890 remainder of the wafer by dicing the wafer (step 264). It is understood by those skilled in the art that many copies of scanners can be produced simultaneously by using conventional microcircuit processing techniques. Thereafter, the individual devices are mounted on bases (step 266) and appropriate

895 electrical connections are made to the pads formed in steps

244-256 (step 268). The result is the desired scanner.

Figures 26, 27a and 27b are detailed views of a moving reflector configuration in accordance with the present invention. Figure 26 is a side view of the configuration. Light 270 emitted 900 from the laser diode 116 is reflectively coUimated by the holographic optical element 272 which is made of deposited aluminum or other dielectric reflector. The holographic optical element 272 is fabricated on a transparent glass wafer 274 as will be discussed below. The glass wafer 274 is suspended above 905 the thin film 60 by flip chip solder balls 276. Light reflected and coUimated by the holographic optical element 272 is directed to the central scanning plate mirror 68 from which it is directed through the transparent glass wafer 274 to the object being imaged. 910 Figure 27a is a top view of the glass wafer 274. A reflective covering 278 prevents stray light emission from the laser diode 116. The holographic optical element 272 is fabricated on the reflective covering 280.

Figure 27b is a top view of the thin film 60. An additional

915 stationary photodetector 282 connects to a pickup 284 for electrical connection. This detector picks up light that is reflected off the imaged object. The configuration of photodetector 56 and electrode 58 is identical to that in Figure

2.

920 Figures 28 and 29 are detailed views of a moving reflector image dissector scanner configuration in accordance with the present invention. Figure 28 is a side view of the configuration. The device in Figures 28 and 29 is identical to that in Figure 26 except for the light path 93, the radiation

925 detector 126 and the stationary radiation emitter 282 with an associated electrode 284.

Figure 29 is a top view of the thin film 60. An additional stationary radiation emitter 282 connects to an electrode 284 for electrical connection. The radiation emitter 282 illuminates the 930 subject being imaged. The lower electrode configuration is identical to that in Figure 2a. The electrode base 147 corresponds to 34 in Figure 2a.

Figures 30a-d are a flow chart of another exemplary process for producing an illustrated embodiment of the present invention.

935 The steps in the exemplary process are generally conventional steps in a conventional process familiar to those skilled in the art of producing microelectronic circuitry. The process begins with a wafer of n-doped silicon material sliced from an appropriately produced boule (step 300).

940 A photoresist is then deposited on the silicon wafer (step 302) and exposed to mask la (Figure 31) (step 304). The photoresist is then developed (step 306). The silicon wafer is then ion implanted (step 308) to create a p-doped region according to the areas exposed by the developed photoresist. The

945 photoresist is then stripped (step 310) from the silicon wafer. Steps 302 through 310 form a p-doped region 285 which will electrically isolate the n-p junction photodiode 126 from the surrounding wafer.

A photoresist is then deposited on the silicon wafer (step

950 312) and exposed to mask 2a (Figure 32) (step 314). The photoresist is then developed (step 316). The silicon wafer is then ion implanted (step 318) to create an n-doped region according to the areas exposed by the developed photoresist. The photoresist is then stripped (step 320) from the silicon wafer.

955 Steps 312 through 320 form an n-doped region 286 which will become the n-side of the n-p junction photodetector from the silicon wafer. A layer of polysilicon is deposited on the face of the silicon wafer (step 322) . A photoresist is then deposited on the

960 silicon wafer (step 324) and exposed to mask 3a (Figure 33) (step 326). The photoresist is then developed (step 328). The layer of polysilicon is then etched (step 330) according to the areas exposed by the developed photoresist. The photoresist is then stripped (step 332) from the layer of polysilicon. Steps 322

965 through 332 form a polysilicon layer with through etched area 288 which is cleared for the n-p junction photodiode 126, areas 290 which are cleared for through holes for lead connectivity to lower electrostatic actuator electrodes and areas 291 for gimbal construction.

970 A layer of thin silicon nitride is deposited on the face of the silicon wafer (step 334). A photoresist is then deposited on the silicon wafer (step 336) and exposed to mask 4a (Figure 34) (step 338). The photoresist is then developed (step 340). The layer of thin silicon nitride is the etched (step 342)

975 according to the areas exposed by the developed photoresist. The photoresist is then stripped (step 344) from the layer of thin silicon nitride. Steps 334 through 344 form an insulating layer with through holes 292 cleared for access to the n-p junction isolated photodetector 126.

980 A layer of aluminum is deposited on the face of the silicon wafer (step 346) . A photoresist is then deposited on the silicon wafer (step 348) and exposed to mask 5a (Figure 35) (step 350). The photoresist is then developed (step 352). The layer of aluminum is then etched (step 354) according to the areas exposed 985 by the developed photoresist. The photoresist is then stripped (step 356) from the layer of aluminum. Steps 346 through 356 form a conductor 293 from the n-doped region of the n-p photodetector, a conductor 294 for the p-doped region of the n-p photodetector, flip chip bonding pads 295, and the scanning 990 mirror reflective surface 296.

The silicon wafer is then rotated to process the backside of the silicon wafer (step 358) . A photoresist is then deposited on the backside of the silicon wafer (step 360) and exposed to mask 6a (Figure 36) (step 362). The photoresist is then

995 developed (step 364). The silicon wafer is then etched (step

366) through to the polysilicon layer according to the areas exposed by the developed photoresist. The photoresist is then stripped (step 368) from the silicon layer backside. Steps 358 through 368 form a deep well 297 from the backside of the wafer

1000 to the polysilicon layer. This deep well 297 permits the gimbal to rotate out of plane of the polysilicon layer in addition to providing lead access to the lower electrostatic actuator pads.

Next, the silicon wafer is diced (step 370) to separate the individual scanner units for further processing.

1005 The lower layer containing the electrostatic actuator electrodes is formed on a glass wafer 298 of similar dimensions to the silicon wafer used in steps 300-370.

A layer of aluminum is deposited on the face of the glass wafer (step 374). A photoresist is then deposited on the glass

1010 wafer (step 376) and exposed to mask 7a (Figure 37) (step 378).

The photoresist is then developed (step 380). The layer of aluminum is the etched (step 382) according to the areas exposed by the developed photoresist. The photoresist is then stripped

(step 384) from the layer of aluminum. Steps 374 through 384

1015 form the lower electrostatic electrodes 430, 432, 434 and 436. The glass wafer is then diced (step 386) to the same dimensions as the silicon wafer scanner components diced in step 370.

The upper layer containing the optical elements of the 1020 scanner are formed on a smaller glass wafer relative to the silicon wafer used in steps 300-370. This glass wafer is then rotated to permit backside processing (step 372).

A layer of aluminum is deposited on the back face of the silicon wafer (step 392) . A photoresist is then deposited on the 1025 glass wafer (step 394) and exposed to mask 8a (Figure 38) (step 396). The photoresist is then developed (step 398). The layer of aluminum is then etched (step 400) according to the areas exposed by the developed photoresist. The photoresist is then stripped (step 402) from the layer of aluminum. Steps 392 1030 through 402 form the flip chip bonding pads 438 for eventual assembly use. The glass wafer is then rotated to the front side for further processing.

A layer of aluminum is deposited on the front face of the glass wafer (step 406). A photoresist is then deposited on the 1035 glass wafer (step 408) and exposed to mask 9a (Figure 39) (step 400). The photoresist is then developed (step 412). The layer of aluminum is then etched (step 414) according to the areas exposed by the developed photoresist. The photoresist is then stripped (step 416) from the layer of aluminum. Steps 406 1040 through 414 form the reflective opaque area 440, the holographic optical element 442 and the clear area 444.

Finally, the smaller glass wafer is diced to a dimension slightly smaller than the wafers diced in steps 370-386. Final assembly of the device includes mounting the diced lower -*

1045 electrode chip formed in steps 372-386 to the diced silicon chip fabricated in steps 300-370. The chips are aligned and bonded using adhesives, welding or electrobonding techniques known in prior art. The backside of the upper optical chip of the device is bonded with the front side of the diced silicon chip (step 1050 422) . The bonding method used is flip chip bonding which is known in prior art. The bonding pads formed in steps 350 and 396 are used in the flip chip bonding process.

The entire assembly is then bonded to a packaging assembly (step 426) with the scanning mirror 88 exposed to the outer 1055 environment. Finally, lead wires are bonded (step 428) to the assembly for connection to external devices.

Figures 40a and 40b are top views of the silicon chip and upper optical chip respectively. This device is very similar to the device illustrated in Figures 29 and 29a, respectively. The 1060 differences are the absence of the radiation source 282, the associated electrode 284, and the addition of a junction isolated n-p junction photodetector 450 with ground lead 452 and active lead 454. Photodetector 450 is made from n-doped silicon and active lead 454 is made from p-doped silicon. This configuration 1065 prevents electrical interference from actuator signals.

Figure 41 is a top view of an array of individual copies of the scanning device of the present invention. The array 450 can typically consist of a rectangular orientation of the scanning devices, which share their edges with other copies of the 1070 scanning devices. The individual copies of the scanning devices can be operated separately, or under coordinated control of a controller, such as a programmed computer to achieve such effects as pseudo-three-dimensional visual displays. Similarly, an array ---

450 of the scanning devices can much more rapidly sample a visual

1075 scene than can an individual scanner.

Figure 41a is a close-up view of a portion of the array 450 shown in Figure 40. As can be seen by reference to Figure 41a, the individual copies of the inventive scanner have the features of an individual scanner, such as that shown in Figure 1.

1080 It will thus be seen that the objects set forth above, and those made apparent in the foregoing description, are effectively attained and since certain changes may be made in the above construction without departing from the scope of the invention, all matters contained in the foregoing description or shown in

1085 the accompanying drawings should be interpreted as illustrative and not in a limiting sense.

It is also understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of

1090 the invention which, as a matter of language, might be said to fall therebetween.

Claims

1. A scanning device, comprising: a substrate; a flexible joint located above the substrate; a support attached to the flexible joint; an actuator formed on at least one of the substrate, the flexible joint and the support, the actuator being able to cause the support to move relative to the substrate; and a radiation collimating element on the upper surface of the support.

2. The scanning device of claim 1 wherein the optical element is a radiation detecting device, the scanning device further comprising at least one electrical conductor passing from the substrate to the radiation detecting device.

3. The scanning device of claim 2, further comprising a radiation collimator that collimates radiation before the radiation reaches the radiation detecting device.

4. The scanning device of claim 3 wherein the collimator is a cylindrical aperture formed in the support, the axial dimension of the cylindrical aperture being many times longer than the largest dimension of the cylindrical aperture in any direction perpendicular to the axial dimension of the cylindrical aperture.

5. The scanning device of claim 1 wherein the optical element is a coUimated radiation-emitting device, the scanning device further comprising at least one electrical conductor passing from the substrate to the coUimated radiation -emitting device.

6. The scanning device of claim 5 wherein the coUimated radiation-emitting device is a laser.

7. The scanning device of claim 6 wherein the laser is a semiconductor laser formed in the support.

8. The scanning device of claim 1 wherein the optical element is a radiation-reflective device.

9. The scanning device of claim 8 wherein the radiation-reflective device is combined with an integrated stationary coUimated radiation emitter.

10. The scanning device of claim 8 wherein the radiation-reflective device is combined with an integrated stationary coUimated radiation detector.

11. The scanning device of claim 1 wherein the actuator includes an electrostatic transducer for converting an electrical signal into electrostatic energy.

12. The scanning device of claim 1 wherein the actuator includes a transducer for converting an electrical signal into thermal energy.

13. The scanning device of claim 1 wherein the actuator includes a piezoelectric transducer for converting an electrical signal into mechanical energy.

14. The scanning device of claim 1 wherein the actuator includes a transducer for converting an electrical signal into electromagnetic energy.

15. The scanning device of claim 11, wherein the support includes a central member having four arms formed in two pairs, the transducer being able to act on each of the pairs of opposing arms independently.

16. The scanning device of claim 1 wherein the flexible joint allows the actuator to cause at least one of the substrate, the flexible joint and the support to move in at least one dimension.

17. The scanning device of claim 13 wherein the flexible joint incudes a gimbal joint formed between the substrate and the support, the gimbal joint allowing the support to move in two dimensions relative to the substrate.

18. The scanning device of claim 13 wherein the flexible joint incudes a spiral spring suspension formed between the substrate and the support, the spiral spring suspension allowing the support to move in two dimensions relative to the substrate.

19. The scanning device of claim 13 wherein the flexible joint includes a structure that is attached to and rises above the 90 substrate.

20. The scanning device of claim 1 wherein the optical element is responsive to at least two separate wavelength of radiation, and produces signals representative of its responses to the at

95 least two wavelengths of radiation.

21. A method for forming a scanning device, comprising the steps of: a) forming a substrate; 100 b) forming a flexible joint over the substrate, the flexible joint being made from a second material]; c) attaching a support to the flexible joint; d) forming an actuator on at least one of the substrate, the flexible joint and the support, the actuator being able to

105 cause the support to move relative to the substrate; and e) forming a radiation collimating element on the upper surface of the support.

110 22. A scanning device, comprising: a substrate made from a first material; a flexible joint located above the substrate, the flexible joint being made from a second material; a support attached to the flexible joint, the support being 115 made from a third material; an actuator formed on at least one of the substrate, the flexible joint and the support, the actuator being able to cause the support to move relative to the substrate; and an optical element on the upper surface of the support.

120

23. The scanning device of claim 22 wherein the optical element is a photosensitive device, the scanning device further comprising at least one electrical conductor passing from the 125 substrate to the photosensitive device.

24. The scanning device of claim 23, further comprising a light collimator that collimates light before the light reaches the 130 photosensitive device.

25. The scanning device of claim 24 wherein the collimator is a cylindrical aperture formed in the support, the axial dimension

135 of the cylindrical aperture being many times longer than the largest dimension of the cylindrical aperture in any direction perpendicular to the axial dimension of the cylindrical aperture.

26. The scanning device of claim 22 wherein the optical element 140 is a light-emitting device, the scanning device further comprising at least one electrical conductor passing from the substrate to the light-emitting device.

27. The scanning device of claim 26 wherein the light-emitting 145 device is a laser.

28. The scanning device of claim 27 wherein the laser is a semiconductor laser formed in the support.

150 29. The scanning device of claim 22 wherein the optical element is a light-reflective device.

30. The scanning device of claim 22 wherein the actuator includes a transducer for converting an electrical signal into

155 thermal energy.

31. The scanning device of claim 22 wherein the actuator includes a piezoelectric transducer for converting an electrical signal into mechanical energy.

160

32. The scanning device of claim 22 wherein the actuator includes a transducer for converting an electrical signal into electromagnetic energy.

165 33. The scanning device of claim 32, wherein the support includes a cross-shaped member having four arms formed in two pairs, the transducer being able to act on each of the pairs of opposing arms independently.

170 34. The scanning device of claim 22 wherein the flexible joint allows the actuator to cause at least one of the substrate, the flexible joint and the support to move in at least one dimension.

35. The scanning device of claim 34 wherein the flexible joint 175 incudes a gimbal joint formed between the substrate and the support, the gimbal joint allowing the support to move in two dimensions relative to the substrate.

36. The scanning device of claim 34 wherein the flexible joint 180 incudes a spiral spring suspension formed between the substrate and the support, the spiral spring suspension allowing the support to move in two dimensions relative to the substrate.

37. The scanning device of claim 34 wherein the flexible joint 185 includes a structure that is attached to and rises above the substrate.

38. The scanning device of claim 22 wherein the optical element is responsive to at least two separate wavelength of light, and

190 produces signals representative of its responses to the at least two wavelengths of light.

39. A method for forming a scanning device, comprising the steps of:

195 a) forming a substrate from a first material; b) forming a flexible joint over the substrate, the flexible joint being made from a second material; c) attaching a support to the flexible joint, the support being made from a third material;

200 d) forming an actuator on at least one of the substrate, the flexible joint and the support, the actuator being able to cause the support to move relative to the substrate; and e) forming an optical element on the upper surface of the support.