WO2009151558A1

WO2009151558A1 - Semiconductor laser packages

Info

Publication number: WO2009151558A1
Application number: PCT/US2009/003415
Authority: WO
Inventors: Satish C. Chaparala; Lawrence C. Hughes, Jr.
Original assignee: Corning Incorporated
Priority date: 2008-06-09
Filing date: 2009-06-05
Publication date: 2009-12-17
Also published as: TW201014091A

Abstract

A laser package may include a metallic platform, a laser diode mounting insert, a liquid crystal polymer header, an electrical interconnect, a laser diode, an optical crystal, and coupling optics. The laser diode mounting insert, coupling optics and optical crystal are coupled to the metallic platform. The electrical interconnect may have conductive pads positioned on an internal portion of the electrical interconnect and conductive traces originating from the conductive pads and running across an external portion of the electrical interconnect. The internal portion may be coupled to the metallic platform. The laser diode may be mounted to the laser diode mounting insert. The coupling optics may be configured to redirect the output beam toward the optical crystal. The liquid crystal polymer at least partially encloses the metallic platform. The liquid crystal polymer may be coupled to the metallic platform and electrical interconnect via an adhesive promoter.

Description

SEMICONDUCTOR LASER PACKAGES

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application

Serial No. 61/059,927, filed June 9, 2008.

BACKGROUND Field

[0002] The present disclosure generally relates to semiconductor packages.

More specifically, some embodiments of the present disclosure relate to semiconductor laser packages and schemes for fabricating and assembling such packages.

Technical Background

[0003] Semiconductor lasers have stringent requirements for reliable packaging. The package serves as the thermal, electrical, optical and system mechanical interface for the laser. As a result, it may be very difficult to package semiconductor lasers properly. The package must maintain stable alignment of the laser with any internal optics and interface with external systems for the life of the semiconductor laser package and provide stable operation over a wide temperature range.

[0004] Conventional semiconductor laser packages may consist of metal or ceramic enclosures that contain the semiconductor laser and any associated optical and electrical elements. The use of metal or ceramic is convenient and has been shown to provide stable operation and long life. However, metal and ceramic enclosures are costly to fabricate and process, and have certain physical properties that create limitations (minimum feature size, lead resistance, thermal conductivity (in the case of ceramic)) in device performance and feature design. Also, most metal and ceramic packages consist of arrangements of structures that can easily be machined or slip cast, usually planar or cylindrical in nature. This limits such packages in the types of features that can be reasonably and economically accommodated within the package structure. The addition of internal or external mechanical reference structures, component mounting features, and other features to aid manufacturing and assembly greatly increases the package complexity and cost.

BRIEF SUMMARY

[0005] In one embodiment, a laser package includes a metallic platform, a laser diode mounting insert, a liquid crystal polymer header, an electrical interconnect, a laser diode, an optical crystal, and coupling optics. The laser diode mounting insert has a thermal conductivity that is greater than a thermal conductivity of the metallic platform, and is coupled to the metallic platform in an optical component region. The electrical interconnect may have conductive pads positioned on an internal portion of the electrical interconnect and conductive traces originating from the conductive pads and running across an external portion of the electrical interconnect. The internal portion of the electrical interconnect may be coupled to the component face of the metallic platform. The laser diode may be mounted to the laser diode mounting insert and electrically coupled to the conductive pads. The coupling optics may be configured to redirect the output beam toward the optical crystal, which is in an optical path of the redirected output beam. The liquid crystal polymer at least partially encloses the metallic platform, the internal portion of the electrical interconnect is maintained within a partially enclosed portion of the metallic platform, and the external portion of the electrical interconnect is maintained external to the partially enclosed portion of the metallic platform. The liquid crystal polymer may be coupled to the metallic platform and the electrical interconnect via an adhesive promoter.

[0006] Additional features and advantages will be set forth in the detailed description which follows and, in part, will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments as described herein, including the detailed description which follows, the claims, as well as the appended drawings. It is to be understood that both the foregoing general description and the following detailed description present embodiments of the disclosure and are intended to provide an overview or framework for understanding the nature and character of the invention as it is claimed. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0007] The following detailed description of specific embodiments can be best understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which:

[0008] Fig. IA illustrates a front perspective view of an exemplary semiconductor laser package according to one or more embodiments;

[0009] Fig. IB illustrates a front perspective view of an exemplary metallic platform according to one or more embodiments;

[0010] Fig. 1C illustrates a front perspective view of an exemplary metallic platform, an exemplary laser diode insert and an exemplary laser diode according to one or more embodiments;

[0011] Fig. ID illustrates the assembly of Fig. 1C with an exemplary electrical interconnect according to one or more embodiments;

[0012] Fig. IE illustrates the assembly of Fig. ID with exemplary coupling optics and optical crystal according to one or more embodiments; and

[0013] Fig. IF illustrates the assembly of Fig. IE with an exemplary liquid crystal polymer header according to one or more embodiments.

DETAILED DESCRIPTION

[0014] Referring initially to Fig. IA, the present disclosure relates generally to semiconductor laser packages. Embodiments retain the benefits of both metal and ceramic package structures by utilizing a package structure having both metal and liquid crystal polymer components that permit the inclusion of multiple mechanical features, compact size, ease of assembly and low cost while retaining critical device performance characteristics such as low thermal impedance, opto-mechanical stability, and electrical impedance.

[0015] Fig. IA illustrates a semiconductor package 100 in which a unifying metallic platform 10 is utilized as a rigid structure upon which the semiconductor laser die and supporting optical and electrical components are assembled. A liquid crystal polymer header 50 is attached to the metallic platform and, along with a lid 60, partially encloses the metallic platform 10 and the components maintained within. The metallic platform 10 is combined with an electrical interconnect 30 that may be, but is not limited to, flexible circuits, stamped or etched leadframes, or printed circuit structures to provide electrical connection to the semiconductor laser and other components within the package. This permits batch processing of the components during manufacturing, assembly and test resulting in reduced costs associated with those operations. As described below, the metallic platform 10 may comprise some or all of the features for mounting and attachment of components within the package and some or all of the mechanical references for use in external systems, such as a semiconductor laser projector, for example.

[0016] In the configuration depicted in Fig. IE, a near infrared output beam emitted by the semiconductor laser 20 is coupled into a waveguide portion of an optical crystal, such as a second harmonic generating crystal, by coupling optics 41, which may include a MEMS mirror assembly 46, and a lens assembly 43 having a lens 42. This configuration illustrated in Fig. IE may be particularly useful in generating a variety of shorter wavelength laser beams from a variety of longer wavelength semiconductor lasers and may be used, for example, as a visible laser source in a laser projection system.

[0017] Referring now to Fig. IB, an exemplary metallic platform 10 is illustrated. The metallic platform 10 may be fabricated by metal injection molding (MIM) in which metal and plastic binders are injected into a mold of the metallic platform. The metallic platform 10 may be made of stainless steel or a metal having high magnetic permeability (e.g., a metal having 70% or greater Ni with a remainder of Fe) to magnetically shield components within the semiconductor laser package 100. As described below, the use of a laser diode insert (22, Figs. 1C- IF) permits the metallic platform 10 to be fabricated from a relatively inexpensive metal having less demanding thermal characteristics.

[0018] Metal injection molding may also permit the selection of different materials aiding in the tailoring of opto-mechanical and thermal properties. Multiple cavity molding of the unit base would result in cavity runners from the injection molding process. These runners are typically removed from the component after processing. These runners can be used to retain the relationship of the individual components after molding and hence permit array processing of the unit metallic platform 10 in subsequent assembly operations. Further, metal injection molding permits multiple metallic platforms to be fabricated in an array, which may be useful during the assembly process.

[0019] The illustrated exemplary metallic platform 10 is generally rectangular in shape and comprises a plurality of features used to assemble and mount the laser diode and its associated components. As the metallic platform 10 may be formed by MIM processes, the metallic platform 10 (including its features) may be monolithic in nature. Features may include mounting bosses, cavities, angles and sloped surfaces, undercuts where permitted, holes, threads, slots and combinations thereof. Features are not limited to the interior or top surface as the exterior of the base may also include features to attach the cover or lid of the component, align the component for subsequent manufacturing steps or be used within a system to mount the completed component.

[0020] Referring now to specific exemplary features of the metallic platform

10 illustrated in Fig. IB, an optical component region 14 may be formed on a component face 12 of the metallic platform 10 during the MIM process. The optical component region 14 may be used to maintain one or more optical components within the metallic platform 10. In the illustrated embodiment, the optical component region 14 is defined by a cavity and magnetic shielding walls 19. The cavity comprises a laser diode cavity 15 and an optical component cavity 16. An area surrounding the laser diode cavity 15, the optical component cavity 16 and the magnetic shielding walls 19 defines a ledge 17 in which additional components may be mounted, such as an electrical interconnect and optical crystal,as described in more detail below. Although the optical component region 14 illustrated in Fig. IB is depicted as a cavity, it is not limited thereto. For example, the optical component region 14 may also be defined by a plurality of bosses, grooves, slots or other similar features configured to locate and maintain optical components within the optical component region 14.

[0021] The exemplary metallic platform 10 further comprises a rear wall surface 13 and front ledge 11 formed during the MIM process. The front ledge 1 1 defines a bottom portion of an opening through which the output beam exits the semiconductor laser package 100. Additional features may also be provided in the metallic platform 10 such as ridges, grooves and holes to aid in coupling the liquid crystal polymer header 50 to the metallic platform 10, locating the semiconductor laser package 100 into a larger assembly, and providing locating features during the assembly process.

[0022] Rather than fabrication by MIM, the metallic platform 10 may also be fabricated through the use of insulated metal substrate materials (IMS). Insulated metal substrates are laminate structures composed of metal base layer overcoated with a dielectric layer. Metal conductors are then deposited on the surface of the dielectric layer. The dielectric layer serves to insulate the conductors from the metallic platform 10. The metal would have the requisite structures (holes, cavities etc) for the diode assembly as well as some or all of the electrical interconnects for the laser diode and its associated components.

[0023] Fig. 1C illustrates an exemplary metallic platform 10 populated with an exemplary laser diode insert 22 and a laser diode 20 in the laser diode cavity 15. The exemplary laser diode insert 22 is configured as a having a generally rectangular shape with a height that approaches the ledge 17 of the component face 12 of the metallic platform 10. It will be understood that other geometric configurations may also be utilized. The laser diode 20 may be coupled to the laser diode insert 22 by solder, use of an adhesive agent, or other similar attachment means. The attachment method chosen should allow for the cathode (or anode in some embodiments) of the laser diode 20 to be electrically connected to the laser diode insert 22. Similarly, the attachment method utilized to attach the laser diode insert 22 to the metallic platform 10 should permit electrical conductivity between the laser diode 22 and the metallic platform 10.

[0024] The laser diode insert 22 should be made of a metallic material having a thermal conductivity that permits heat generated by the laser diode 20 to be transferred to the laser diode insert 22 and dissipated such that the laser diode insert 22 acts as a heat sink. Use of a laser diode insert 22 having such thermal conductivity allows for the metallic platform 10 to be made of a relatively less costly material because heat sink functionality may be enabled by the laser diode insert 22 rather than the entire metallic platform 22. The material chosen for the laser diode insert 22 should also have a coefficient of thermal expansion that is similar to the coefficient of thermal expansion of the laser diode 20 so that the mating relationship between the laser diode 20 and the laser diode insert 22 may be maintained during operation of the semiconductor laser package 100. Exemplary materials include WCu, AlSiC and AlN among others.

[0025] The laser diode 20 may be configured as any type of semiconductor laser configured to emit an output beam, such as a distributed feedback (DFB) laser, a distributed Bragg reflector (DBR) laser, a vertical cavity surface-emitting laser (VCSEL), a vertical external cavity surface-emitting laser (VECSEL) or a Fabry- Perot laser, for example. The laser diode insert 22 may comprise locating features to aid in coupling the laser diode 20 to the laser diode insert 22 during assembly. Other features may also be provided to align the laser diode 20 with other optical components within the semiconductor laser package 100. In the illustrated embodiment, the laser diode insert 22 comprises a mounting surface 24 that is slightly angled with respect to the ledge 17 of the metallic platform 10 to angle the output beam emitted by the laser diode 20.

[0026] Electrical connections between the laser diode 20, coupling optics 41

(see Fig. 1 E), the metallic platform 10 and any other electrical components may be effectuated by an electrical interconnect 30. The electrical interconnect 30 may be configured as a flexible circuit having conductive traces (e.g., traces 36), conductive pads (e.g., pads 32), vias (e.g., via 34), ground planes, and other features. The electrical interconnect 30 may be a two layer flexible circuit having conductive features on both a top and bottom surface. In another embodiment, the electrical interconnect 30 may be configured as a leadframe that is coupled to the metallic platform 10.

[0027] The electrical interconnect 30 illustrated in Fig. ID may be coupled to the metallic platform 10 on the ledge 17 by adhesive, solder or compression such that certain electrical features are electrically coupled to the metallic platform 10 (e.g., ground planes and traces). The electrical interconnect 30 may be geometrically configured to wrap around features of the metallic platform 10 to permit rapid and easy assembly of the electrical interconnect 30 to the ledge 17 of the metallic platform 10. Since the metallic platform 10 may be fabricated in an array, the electrical interconnect 30 may also be fabricated in a corresponding array, thereby permitting multi-up attachment of the electrical interconnect 30 to the metallic platform 10. An internal portion of the electrical interconnect 30 comprises a plurality of conductive pads 32 to support the interconnect requirements of the laser diode 20, coupling optics 41, and any other associated components. For example, connections between the laser diode 20 and the conductive pads 32 may be made by a wire from laser diode 20 connection to the conductive pads 32. An external portion of the electrical interconnect 30 may be configured to meet any system level connection requirements such that the semiconductor laser package 100 may be electrically connected to other components in a larger system. External connection to system level components may be via the use of industry standard zero insertion force connectors, pin headers, or soldered flex arrangements, for example.

[0028] Fig. IE illustrates the metallic platform 10 populated with an optical crystal 40 and coupling optics 41 comprising a lens assembly 43 and a MEMS mirror assembly 46 in addition to the laser diode 20 and laser diode insert 22. The optical crystal 40 may be used to convert a native output beam generated by the laser diode 20 into higher harmonics. For example, the optical crystal 40 may be configured as a SHG crystal or a higher harmonic generating crystal to frequency-double an output beam generated by the laser diode 20 having a native wavelength in the infrared or near infrared band. For example, a SHG crystal, such as an MgO-doped periodically poled lithium niobate (PPLN) crystal, may be used to generate green light by converting the wavelength of a 1060nm DBR or DFB laser to 530 nm. The optical crystal 40 may be mounted onto the ledge 17 of the metallic platform 10 such that an input facet faces the lens assembly 43 and an output facet faces the opening (see 57 Fig. IF) through which the output beam may exit the semiconductor laser package 100. As illustrated in Fig. IE, the optical crystal 40 may be mounted in a plane that is above the laser diode 20. The optical crystal 40 may be coupled to the ledge 17 by adhesive, frit or other similar attachment means. In some embodiments, the optical crystal 40 may be maintained in a crystal heat sink assembly (not shown) that is then attached to the metallic platform 10. [0029] In the illustrated embodiment, the coupling optics 41 (lens assembly 43 and MEMS mirror assembly 46) is positioned within the coupling optics cavity 16 in an optical path of the output beam generated by the laser diode 20. The MEMS mirror assembly 46 and lens assembly 43 may be coupled to the metallic platform 10 by adhesive, solder, frit or mechanical attachments such as screws, clips or the like. In the optical configuration illustrated in Fig. IE, the lens assembly 43 and MEMS mirror assembly are positioned within the metallic platform 10 such that a relatively compact, folded-path optical configuration is provided. The lens assembly 43 comprises a lens housing 44 and a lens 42. The MEMS mirror assembly 46 may be configured to fold the optical path such that the optical path of the output beam of the laser diode 20 initially passes through the lens assembly 43 to reach the MEMS mirror assembly 46 as a collimated or nearly collimated beam and subsequently returns through the same lens assembly 43 to be focused on an input facet of the optical crystal 40 by the lens 42. In this configuration, the optical path is "folded" as the output beam emitted by the laser diode 20 is initially directed through the lens assembly 43 and then reflected back through the same lens assembly 43. It is noted that reference herein to a "collimated or nearly collimated" beam is intended to cover any beam configuration where the degree of beam divergence or convergence is reduced, directing the beam towards a more collimated state.

[0030] The lens assembly 43 can be described as a dual function, collimating and focusing lens 42 because it serves to collimate the divergent light output of the laser diode 20 and then refocus the laser light propagating along the optical path of the semiconductor laser package 100 into the optical crystal 40. This dual function optical component is well suited for applications requiring magnification factors close to one because a single coupling optics assembly 41 is used for both collimation and focusing.

[0031] The MEMS mirror assembly 46 comprises a MEMS-actuated mirror

47 that is used to reflect the collimated or nearly collimated output beam back toward the lens 42 of the lens assembly 43. The MEMS may be utilized to adjust the mirror 47 such that the MEMS mirror assembly 46 and lens 42 cooperate to precisely position and focus the redirected output beam onto the input facet of the optical crystal 40. In the illustrated embodiment, the MEMS mirror assembly 46 is partially surrounded by the magnetic shielding walls 19 to prevent electro-magnetic radiation traveling to and/or from the MEMS mirror assembly 46. The MEMS mirror assembly 46 may be connected to conductive pads 32 of the electrical interconnect 30 by way of wires (not shown). Although the exemplary embodiment illustrated in Fig. IE depicts the MEMS mirror assembly 46 and lens assembly 43 as two separate units, other embodiments may utilize a combined assembly that comprises both the MEMS mirror assembly 46 and lens assembly 43 in one integrated package.

[0032] Fig. 1 F illustrates the metallic platform 10 populated with the aforementioned optical and electrical components and a liquid crystal polymer header 50 coupled thereto. The use of liquid crystal polymer for the header 40 may provide high resistance to thermal degradation, stress fractures and other mechanical or environmental failures. The liquid crystal polymer header 50 partially surrounds the metallic platform 10 and the components maintained thereon such that the semiconductor laser package 100 comprises a top opening 58 and an output beam opening 57. In some embodiments, a transparent material may be positioned within the output beam opening 57. The output beam opening 57 may be defined by header walls 52 and 54, metallic platform front ledge 11 and a top header portion 59. The top opening 58 may be formed in a top surface 56 of the liquid crystal polymer header 50. The top opening 58 provides access to the components maintained within the semiconductor laser package 100.

[0033] The liquid crystal polymer header 50 may be coupled to the metallic platform by an overmolding procedure. The liquid crystal polymer may be molded over the metallic platform 10 to achieve the desired shape of the liquid crystal polymer header 50. The metallic platform 10 may comprise features that aid in the molding of the liquid crystal polymer header 50 over the metallic platform 10. As liquid crystal polymer may resist adhering to other materials, an adhesion promoter may be utilized to ensure that the liquid crystal polymer adheres to the metallic platform 10. The adhesion promoter may be applied to the vertical walls of the metallic platform 10 as well as to areas of the electrical interconnect 30 that interface with the liquid crystal polymer header 50 such as region 53. The external portion of the electrical interconnect 30 extends out from the liquid crystal polymer header 50, and portions of the electrical interconnect 30 are encapsulated by the liquid crystal polymer header 50.

[0034] In other embodiments, the liquid crystal polymer header 50 may be coupled to the metallic platform 10 mechanically rather than by an overmolding process. For example, the metallic platform 10 and a previously molded liquid crystal polymer header 50 may comprise mating mechanic features such that the liquid crystal polymer header 50 may be coupled to the metallic platform 10. Further, an adhesive and adhesive promoter may couple the liquid crystal polymer header 50 to the metallic platform 10. After the liquid crystal polymer header 50 is coupled to the metallic platform 10, the optical crystal 40, laser diode 20, laser diode header 22, lens assembly 43 and MEMS mirror assembly 46 may be attached to the metallic platform 10.

[0035] Referring once again to Fig. IA, the semiconductor laser package 100 may also comprise a lid 60 that covers the top opening 58 of the liquid crystal polymer header 50. A soft seal or a grommet may be positioned around the perimeter of the top opening 58 such that the lid 60 may cooperate with the top opening 58 to exclude environmental contaminates such as dirt, dust, etc. Although Fig. IA illustrates a flat stepped lid 60, other embodiments may utilize a lid having a hinge such that the lid may be opened and closed, or an interlocking lid to provide a locking feature. Accidental removal of the lid 60 may be prevented by applying an adhesive as a locking agent. An additional degree of seal integrity can be obtained by applying a suitable polymer around the perimeter of the package after locking the lid to the package.

[0036] As described above, embodiments of the present disclosure may provide a semiconductor laser package that is suitable for consumer applications that is cost effective, has reduced fabrication and assembly costs, and is reliable and durable. Embodiments combine a cost effective metallic platform, a laser diode insert for improved thermal performance, a liquid crystal polymer header for increased mechanical and environmental survivability and a electrical interconnect for increased interconnect performance. Embodiments may be incorporated in a wide variety of consumer products, such as laser projectors. [0037] It is noted that terms like "preferably," "commonly," and "typically," if utilized herein, should not be read to limit the scope of the claimed invention or to imply that certain features are critical, essential, or even important to the structure or function of the claimed invention. Rather, these terms are merely intended to highlight alternative or additional features that may or may not be utilized in a particular embodiment of the present invention.

[0038] For the purposes of describing and defining the present invention it is noted that the term "substantially" is utilized herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. The term "substantially" is also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue.

[0039] It is noted that recitations herein of a component of the present invention being "configured" in a particular way, "configured" to embody a particular property, or function in a particular manner, are structural recitations as opposed to recitations of intended use. More specifically, the references herein to the manner in which a component is "configured" denotes an existing physical condition of the component and, as such, is to be taken as a definite recitation of the structural characteristics of the component.

[0040] It is noted that one or more of the following claims utilize the term

"wherein" as a transitional phrase. For the purposes of defining the present invention, it is noted that this term is introduced in the claims as an open-ended transitional phrase that is used to introduce a recitation of a series of characteristics of the structure and should be interpreted in like manner as the more commonly used open- ended preamble term "comprising."

[0041] Having described the invention in detail and by reference to specific embodiments thereof, it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims. More specifically, although some aspects of the present invention are identified herein as preferred or particularly advantageous, it is contemplated that the present invention is not necessarily limited to these preferred aspects of the invention.

Claims

1. A laser package comprising a metallic platform, a laser diode mounting insert, a liquid crystal polymer header, an electrical interconnect, a laser diode, an optical crystal, and coupling optics, wherein: the metallic platform comprises an optical component region located on a component face of the metallic platform; the laser diode mounting insert is coupled to the component face of the metallic platform within the optical component region; the laser diode is mounted to the laser diode mounting insert is operable to emit an output beam; the electrical interconnect is coupled to the component face and comprises a plurality of conductive pads positioned on an internal portion of the electrical interconnect, and a plurality of conductive traces originating from respective conductive pads and traversing the electrical interconnect across an external portion of the electrical interconnect; the coupling optics is coupled to the component face of the metallic platform within the optical region in an optical path of the output beam and is configured to redirect the output beam toward the optical crystal; the optical crystal is coupled to the component face of the metallic platform in an optical path of the redirected output beam; the liquid crystal polymer header at least partially encloses the metallic platform, the internal portion of the electrical interconnect is maintained within a partially enclosed portion of the metallic platform, and the external portion of the electrical interconnect is maintained external to the partially enclosed portion of the metallic platform; and the liquid crystal polymer is coupled to the metallic platform and the electrical interconnect via an adhesive promoter.

2. A semiconductor laser package as claimed in claim 1 wherein the laser diode mounting insert is made of WCu, AlSiC or AlN.

3. A semiconductor laser package as claimed in claim 1 wherein the laser diode mounting insert is coupled to the metallic platform with an adhesive agent.

4. A semiconductor laser package as claimed in claim 1 wherein the laser diode mounting insert is soldered to the metallic platform.

5. A semiconductor laser package as claimed in claim 1 wherein the metallic platform is fabricated by a metal injection molding process.

6. A semiconductor laser package as claimed in claim 1 wherein the metallic platform is an insulated metal substrate assembly.

7. A semiconductor laser package as claimed in claim 1 wherein the metallic platform is monolithic.

8. A semiconductor laser package as claimed in claim 1 wherein the metallic platform comprises 70% or more nickel and a remainder that is substantially iron.

9. A semiconductor laser package as claimed in claim 1 wherein the metallic platform comprises 304 Stainless steel

10. A semiconductor laser package as claimed in claim 1 wherein the optical component region comprises a cavity in which the laser diode mounting insert and the coupling optics are maintained.

11. A semiconductor laser package as claimed in claim 9 wherein the laser package further comprises one or more magnetic shielding walls perpendicular to the component face.

12. A semiconductor laser package as claimed in claim 1 wherein the electrical interconnect is a flexible circuit.

13. A semiconductor laser package as claimed in claim 1 wherein the electrical interconnect is a leadframe assembly.

14. A semiconductor laser package as claimed in claim 1 wherein the liquid crystal polymer header defines a top surface opening of the laser package.

15. A semiconductor laser package as claimed in claim 1 wherein the liquid crystal polymer header is fabricated by a overmolding process in which the liquid crystal polymer header is molded over the metallic base and electrical interconnect.

16. A semiconductor laser package as claimed in claim 1 wherein the liquid crystal polymer header is coupled to the metallic platform by an adhesive and the adhesive promoter.

17. A semiconductor laser package as claimed in claim 1 wherein: the coupling optics comprises a lens and a MEMS mirror; the lens is configured to focus the output beam onto the MEMS mirror; the MEMS mirror is configured to redirect the output beam through the lens; and the lens is further configured to focus the redirected output beam onto the optical crystal.

18. A semiconductor laser package as claimed in claim 17 wherein the metallic base further comprises one or more magnetic shielding walls surrounding the MEMS mirror.

19. A semiconductor laser package as claimed in claim 17 wherein the laser diode, the MEMS mirror, and the optical crystal are oriented on the metallic platform to form a folded optical pathway between an output of the laser diode and an input of the optical crystal such that an output beam of the laser diode may be reflected by the MEMS mirror into the input of the optical crystal;

20. A semiconductor laser package as claimed in claim 1 wherein the optical crystal is a frequency converting lithium niobate crystal.