WO2002075734A2

WO2002075734A2 - Method and device for producing geometrically exact copies of subsets of punctiform locations

Info

Publication number: WO2002075734A2
Application number: PCT/EP2002/002941
Authority: WO
Inventors: Ulrich Rexhausen; Manfred Wick
Original assignee: Lifebits Ag
Priority date: 2001-03-16
Filing date: 2002-03-16
Publication date: 2002-09-26
Also published as: WO2002075734A3; DE10113709A1

Abstract

The invention relates to a method for producing a carrier for conducting a biochemical analysis. To this end, a carrier is produced with a large number of pits that are arranged along a spiral. Copies are produced starting from a master carrier and they contain subsets of the pits of said master carrier. When producing the copies, the pits of the master carrier are read, and the tracking of the laser is corrected according to the arrangement of the pits of the master carrier.

Description

Description:

Method and device for producing geometrically accurate copies of subsets of punctiform points

The invention deals with the problem of spatially exact mapping of subsets of a geometric pattern of structures.

One application in which geometric patterns of structures are to be reproduced exactly is analytical chemistry. Molecules are to be applied to precisely defined, very small places on a single-use carrier. Very complex variations of different molecules are applied to different places. Different molecules are to be applied to different subsets of structures by means of stamping technology, whereby a direct and spatially reproducible addressing of the structures is achieved. Such an arrangement could be used, among other things, for complex analytical detection methods, the majority of which are based on the optical detection of molecular properties. Another application would be the creation of molecular libraries on a support.

According to the current state of the art, one avoids complicated geometrical arrangements and switches to structures arranged in a grid. However, this requires special equipment for the spatially high-resolution optical detection of the molecules on the structures.

It is already known to manufacture such measurement carriers using the methods of producing CDs (compact discs) (WO 00/22677). Masks for the creation of CD masters are sequentially written by means of a laser onto a rotating round glass pane coated with photoresist, in order to produce a glass master. Up to 10 ¹⁰ separate areas are exposed, which are arranged one behind the other on a spiral line. After development of the exposed photoresist, they form small areas, which are referred to as point-shaped locations in the present description. The holes are approximately 150 nm deep. The pit structure of the so-called nickel master is defined through these holes when nickel is deposited on the glass master. The nickel master, also called "father", is copied into a negative nickel master, which is also referred to as "mother" or matrix. The impressions of the negative nickel master form the injection mold for the production of the CDs. Sequential pit patterns can be written with great precision. However, the spiral tracks created in this way have tolerances in the range of 5 μm when the same data stream is written repeatedly, even with the most modern recorders, since the track errors add up over many thousands of tracks. This means that it is not possible to produce congruent masters with partially modulated bit patterns for stamping. CD production using conventional lithography methods, such as is used for microprocessor production, is not easily possible, since the amount of data is difficult to handle due to the requirements for optical resolution, requires a lot of time and is therefore expensive.

In the structure of a CD, in the level of the mirroring there are usually the so-called pits, namely depressions of less than 1 μm in size, which disrupt the mirroring, as well as the so-called lands, i.e. flat mirrored spaces between the pits. These standard structures are used as information carriers and are also used for "tracking", ie the tracking of the reading head. The area occupied by the pits is small compared to the mirrored lands. The pits are recognized by the fact that they do not reflect the light. It is therefore not essential that the pits are depressions. It can also be irregularly shaped elevations or other places where the mirroring is interrupted. For the sake of simplicity, the term "pit" is used here for the non-reflecting areas.

The invention is based on the object of creating a possibility with the aid of which geometrically accurate images of subsets of the punctiform points of a carrier can be produced.

To achieve this object, the invention proposes a method with the features mentioned in claim 1. The invention also proposes a device with the features of claim 8. Further developments of the invention are the subject of dependent claims, the wording of which, like the wording of the abstract, is made by reference to the content of the description.

The invention enables the adaptation of suitable detection carriers for analysis using mass products of consumer electronics such. B. CD players. These are available in large numbers at low prices and are distributed millions of times. Equally suitable as the CD are their further developments, such as CD-ROM, CD-R and DVD as well as magneto-optical and magnetic carriers. In the further description, the term CD is always used synonymously for all such carriers and measuring carriers.

In the prior art, as stated above, the pit patterns are generated by the control of the write laser, no further use of these patterns is provided. According to the invention the previously generated master carrier is used to determine the position of the pits on the submaster by scanning the traces of pits there. In this way, the geometry of the master is exactly passed on to the submaster. The submasters are then used to create stamps for addressing molecules on the structures. As a result, different molecules can be applied and addressed to subsets of the standard structures using stamps. It is also possible to insert newly defined structures that are compatible with the requirements of tracking and information carriers.

In a further development of the invention it can be provided that the punctiform points of the master carrier are produced with the aid of a photosensitive layer which is exposed by a controlled laser in accordance with predetermined data.

However, it is also possible and within the scope of the invention for a master, for example consisting of glass, to be produced by stamping positive / negative photoresist. The properties and uses of such paints are known to the person skilled in the art.

From this stamped glass master, subsets of stamps can then be produced according to the invention by selectively exposing certain punctiform points. As a result, structures can be selectively polymerized or evaporated.

According to the invention, the pits or punctiform points of the master carrier can be produced with the aid of a photosensitive layer (or a photoresist) which is exposed by a controlled laser. Following the exposure, the exposed part can then be chemically dissolved away and the pits can be produced by nickel deposition. In this way, the spiral arrangement of the pits. In addition, an exit mark can be set, which makes it possible to determine the position of a special pit by counting. Known technologies can continue to be used by this type of production.

It is of course also possible to accommodate additional information in the pits, for example a serial number of the measurement carrier, product-specific application software, information about the molecules applied at the respective location, application-related databases and the like.

An example will be discussed in more detail using a spiral arrangement of pits, such as is available on a conventional CD. A modified CD burner, which is able to read glass master discs directly, is used for laser lithography. An already etched glass master disc is placed face to face in the system with a disc coated with non-reflective photoresist (submaster negative). The reading head has a low-energy laser with which it reads the pit track using the conventional method. Each pit is recognized by the different reflective properties of the paints and assigned to the master structure known as the data stream. There is a separate data stream for each submaster that describes the pits to be exposed on the submaster. The submaster data stream is generated and adjusted in real time by the master master based on the read data stream. The high-energy laser is activated briefly in accordance with the submaster data stream, as a result of which a pit is written into the submaster negative. After the submast negative has been developed, it can be copied again, for example by contact exposure, in order to obtain a positive image of the submaster. The control software records the block coordinates for each data block to be mastered, consisting of the track number increasing radially outwards and the offset of the block relative to a zero mark on the carrier. During the subsequent softprinting, this enables the unambiguous assignment of a data block when applying many different substrates by means of a stamp.

Further features, details and advantages of the invention will become apparent from the following description of preferred embodiments of the invention, the patent claims and the drawing. Here show:

1 to 6, the process steps for producing a

Measuring carrier;

7 to 9 process stages for the production of a stamp;

10 to 12 different process stages in a second embodiment;

13 shows a possibility of producing a submaster based on the master structure;

14 shows a further possibility of producing a submaster.

Figure 1 shows schematically and simplified a cross section through a glass master 1, which is coated on one side with a photoresist 2. This forms the output for the creation of a master. The layer 2 of the photoresist is exposed with the aid of a controlled laser, the laser beam exposing point-like locations along one spiral line are arranged. This forms the original spiral shown schematically in FIG. 2.

A father 3 (see FIG. 3) is produced by nickel deposition, which thus represents a negative of the structure of FIG. 2. A further nickel deposition produces a mother structure 4 from the father 3, see FIG. 4. A son structure 5 is produced from the mother structure 4 by a further deposition process. Any number of son structures 5 can be produced. This son structure 5 is used to produce support structures 6 in the form of blank CDs with the aid of injection molding processes, on which all pits are present. This is shown in Figure 6. Any number of supports 6 can also be generated from any number of son structures 5.

FIG. 7 shows how the glass master 1 shown in FIG. 2 exposes a glass master coated with negative photoresist. This results in a (“inverted”) negative substrate 7, which is shown in FIG. 7 above the glass master 1.

With the aid of a laser beam 8, which is focused with conventional optical devices 9, the photoresist layer 10 of a further substrate 11 is partially exposed through the negative substrate 7 (see FIG. 8). From this further substrate 11, which represents a first submaster, a negative for a silicone stamp is produced by depositing nickel stamps or by renewed electroforming. This stamp 12 is shown in FIG. 9. It contains a subset of elevations 13, which are intended for contacting specific subsets of elevations 14 of the measuring carriers 6 shown in FIG. By aligning the punches 12 with the measuring carriers 6 in an aligned manner, detector molecules can be applied to certain elevations or pits of the measuring carrier. By using a large number of stamps with the help of many submasters different detector materials can be applied to the different subsets of pits.

A measuring carrier provided with the detector molecules can then be wetted with a sample to be examined, which depending on the selection of the sample and / or the detector molecules leads to the various chemical or physical processes

Reactions / interactions. The result can then be read out with the aid of a CD device, the assignment between the measurement results and the evaluations being carried out in software.

FIGS. 10 and 11 show an embodiment in which a negative substrate 15 is produced through the master master after coating with negative photoresist and exposure. A negative substrate 18, mirror-image spiral, is produced from the negative substrate 15 by exposure. This negative substrate 18 is used in a similar way to produce a son substrate 16, see FIG. 12, with the aid of which an inverse CD 17 can be produced by injection molding. The pits protrude from the side of the CD facing away from the laser. Starting from the substrate 18, a further substrate can be produced with the original spiral by exposure to a positive photoresist. This can be further processed according to FIGS. 8 and 9 into masters for silicone stamps, which subsets of the "negative" pits protruding from the CD can address.

In a further embodiment of the method, starting from a negative substrate 7, an etching mask is created by congruent mastering, which addresses defined subsets of lands. Applying a photo-resistive layer to a son and then exposing it through the congruent etching mask subsequently permits targeted etching of the son. This creates more defined structures on the son Depth, which after the injection molding on the CD represent increases, which from. protrude from the land plane on the side facing away from the laser. The height of these structures can differ from the depth of the pits. The increase allows greater tolerances both in the manufacture of the stamp and in the alignment of the CD and stamp.

FIG. 13 shows in more detail an alternative method step to the method shown in FIG. 8. A laser double head 20 contains two permanently connected laser heads. A laser head is used to generate a weak reading beam, represented by the double arrow 21. This reading beam 21 reads out the negatively oriented CD master 22. The laser head 20 contains a second strong laser, which generates a write beam 23 in a controlled manner. This write beam 23 can be switched on and off by the logic of the double head 20. A connected computer searches for the subset of the master's pits to be copied and controls the read-write logic. The fixed coupling of the two laser heads, in conjunction with a definition of a parallel alignment to the axis of rotation, ensures a spatial 1: 1 structure of the subset structure of the pits. The actual procedure for manipulating the stamp consists in curing or introducing suitable material into the master stamp structure 24, which is held on the underside of a stamp holder 25, for example by negative pressure. Material present on the underside of the stamp holder 25, for example plastic material, is cured by exposure to the writing beam 23. After the subset of pits has been written completely, the excess material 26 is removed, for example by rinsing with solvent. Tracking is only in the reading direction, since both heads are rigidly connected and the entire head is moved. The focus is adjusted in both arms. FIG. 14 shows a device which is similar to the device according to FIG. 13. It is used here to create a positive sub-copy of a CD master. Connected by the axis 27, the CD master 22 and the sub copy 28 of the CD master to be produced rotate synchronously with one another. The side of the copy 28 facing the laser head 20 is coated with a layer 29 of photoresist which can be exposed by the writing beam 23. A connected computer searches for the subgroup of the master CD pits to be copied and controls the read-write logic. Attention is paid to an adapted focus size of the two beams, namely the reading beam 21 and the writing beam 23. With the same size of the focus of the two beams, this results in a 1: 1 copy of the pits.

Claims

claims:

1. Method of making a geometrically accurate

Image of individually selectable points from a plurality of positions of a measuring carrier (6) arranged according to a predetermined pattern, with the following

Process steps: 1.1 on a substrate to form a master carrier (1) all possible punctiform points are produced, 1.2 at least one measuring carrier (6) with all punctiform points is derived from the master carrier (1), 1.3 from the master carrier (1) is by selective Copy the punctiform places of the master carrier (1) at least one

Submaster carrier (11) generated, 1.3.1 when copying the punctiform points by a laser

Tracking its path is corrected according to the track of the punctiform points on the master carrier (1).

2. The method of claim 1, wherein the punctiform

Places of the master carrier (1) are produced with the aid of a photosensitive layer (2), which is exposed by a controlled laser according to predetermined data.

3. The method according to claim 1 or 2, wherein the master carrier (1), in particular consisting of glass, is produced by stamping positive / negative photoresist.

4. The method of claim 3, wherein the at least one

Submaster carrier by targeted exposure of the stamped Master carrier (1) for the selective polymerization or evaporation of structures is produced.

5. The method according to any one of the preceding claims, wherein the punctiform points are arranged along a spiral.

6. The method according to any one of the preceding claims, wherein the arrangement of the punctiform locations corresponds to the arrangement of the pits of a CD.

7. The method according to any one of the preceding claims, wherein the coordinates of a pit are determined by counting the revolutions of the carrier from a zero mark.

8. Device for producing a geometrically accurate image of individually selectable point-shaped points from a plurality of points of a carrier arranged according to a predetermined pattern

8.1 a laser generating a reading beam (21),

8.2 a laser generating a write beam (23), the

8.3 are mechanically combined to form a laser head (20),

8.4 a holder for the master carrier (22), 8.5 a holder for the copy carrier (24, 28),

8.6 a rotary drive for synchronously driving both brackets,

8.7 a drive for displacing the laser head (20) in the radial direction, and 8.8 a controller for controlling the movement of the drive of the laser head (20) and the two beams (21, 23) of the laser head.