Manufacturable multi-emitter laser diode

• US 9,520,697 B2
• Filed: 01/20/2015
• Issued: 12/13/2016
• Est. Priority Date: 02/10/2014
• Status: Active Grant

• Current Assignee: Kyocera SLD Laser Incorporated (Kyocera Corporation)
• Original Assignee: Soraa Laser Diode, Inc. (Kyocera Corporation)
• Inventors: Steigerwald, Dan, McLaurin, Melvin, Goutain, Eric, Sztein, Alexander, Hsu, Po Shan, Rudy, Paul, Raring, James W.
• Primary Examiner(s): Karimy, Timor
• Application Number:
  US14/600,506
• Publication Number:
  US 20150229108A1
• Time in Patent Office: 693 Days
• Field of Search: 438/33, 438/68, 438/113, 438/460, 438/91, 438/237, 438/458
• US Class Current: 1/1
• CPC Class Codes: H01S 5/005 Optical components external to the laser cavity, specially adapted therefor, e.g. for homogenisation or merging of the beams or for manipulating laser pulses, e.g. pulse shaping H01S5/026, H01S5/18388 take precedence
• CPC Class Codes: H01S 5/0087 for illuminating phosphorescent or fluorescent materials, e.g. using optical arrangements specifically adapted for guiding or shaping laser beams illuminating these materials
• CPC Class Codes: H01S 5/0202 Cleaving
• CPC Class Codes: H01S 5/0203 Etching
• CPC Class Codes: H01S 5/0215 Bonding to the substrate
• CPC Class Codes: H01S 5/0216 using an intermediate compound, e.g. a glue or solder
• CPC Class Codes: H01S 5/0217 Removal of the substrate
• CPC Class Codes: H01S 5/0218 Substrates comprising semiconducting materials from different groups of the periodic system than the active layer
• CPC Class Codes: H01S 5/04253 having specific optical properties, e.g. transparent electrodes
• CPC Class Codes: H01S 5/04256 characterised by the configuration
• CPC Class Codes: H01S 5/04257 having positive and negative electrodes on the same side of the substrate
• CPC Class Codes: H01S 5/22 having a ridge or stripe structure
• CPC Class Codes: H01S 5/34333 with a well layer based on Ga(In)N or Ga(In)P, e.g. blue laser
• CPC Class Codes: H01S 5/4012 Beam combining, e.g. by the use of fibres, gratings, polarisers, prisms
• CPC Class Codes: H01S 5/4031 Edge-emitting structures
• CPC Class Codes: H01S 5/4056 emitting light in more than one direction
• CPC Class Codes: H01S 5/4087 emitting more than one wavelength
• CPC Class Codes: H01S 5/4093 Red, green and blue [RGB] generated directly by laser action or by a combination of laser action with nonlinear frequency conversion

Abstract

A method for manufacturing a multi-emitter laser diode device includes providing a substrate having a surface region and forming epitaxial material overlying the surface region, the epitaxial material comprising an n-type cladding region, an active region comprising at least one active layer overlying the n-type cladding region, and a p-type cladding region overlying the active layer region. The epitaxial material is patterned to form a plurality of dice, each of the dice corresponding to at least one laser device, characterized by a first pitch between a pair of dice, the first pitch being less than a design width. Each of the plurality of dice are transferred to a carrier wafer such that each pair of dice is configured with a second pitch between each pair of dice, the second pitch being larger than the first pitch.

Claims

1. A method for manufacturing a multi-emitter laser device, the method comprising:

providing a substrate member having a surface region;

forming an epitaxial material overlying the surface region, the epitaxial material comprising a release material, an n-type cladding region overlying the release material, an active region comprising at least one active layer overlying the n-type cladding region, and a p-type cladding region overlying the active layer; and

an interface region overlying the p-type cladding region;

forming a plurality of dice by at least patterning the epitaxial material and defining mesa regions to provide a plurality of epitaxial mesa dice regions, each pair of epitaxial mesa dice regions being characterized by a first pitch between the epitaxial mesa dice regions;

subjecting the release material to an energy source to fully or partially remove the release material;

bonding the interface region associated with at least one of the plurality of epitaxial mesa dice regions to a carrier wafer to form a bonded structure wherein at least a pair of bonded epitaxial mesa dice regions are arranged in a substantially parallel configuration on the carrier wafer with a lateral spacing defined by a second pitch;

initiating a release of the substrate member to complete a transfer of the bonded epitaxial mesa dice regions to the carrier wafer to provide transferred epitaxial mesa dice regions on the carrier wafer at the second pitch;

processing the transferred epitaxial mesa dice regions on the carrier wafer to form a plurality of laser stripe regions;

processing the carrier wafer with the plurality of transferred epitaxial mesa dice regions comprising the plurality of laser stripe regions to form a plurality of laser diode regions each configured as a multi-emitter laser diode device;

wherein a pair of the laser diode regions is spaced by a third pitch from an adjacent pair of the laser diode regions; and

singulating each of the plurality of laser diode regions in the multi-emitter laser diode device to form individual laser diode devices.

2. The method of claim 1, wherein the first pitch of the epitaxial mesa dice regions on the substrate member is less than the second pitch of the transferred epitaxial mesa dice regions on the carrier wafer and wherein the second pitch of the transferred epitaxial mesa dice regions is less than the third pitch provided between the adjacent pair of the laser diode regions in the multi-emitter laser diode device.

3. The method of claim 1, wherein the first pitch is between 1 μ

m and 10 μ

m and the second pitch is between 10 μ

m and 50 μ

m, or the first pitch is between 10 μ

m and 50 μ

m and the second pitch is between 25 μ

m and 150 μ

m, or the first pitch is between 50 μ

m and 200 μ

m and the second pitch is between 100 μ

m and 400 μ

m with a length of 50 μ

m to 5000 μ

m.

4. The method of claim 1, wherein the third pitch is between 150 microns and 500 microns, or between 500 microns and 5 millimeters, or between 5 millimeters and 2 centimeters.

5. The method of claim 1, further comprising forming one or more components overlying a space defined by the third pitch, the one or more components being selected from one or more of a metal contact region, a metal interconnect region, or a metal bonding pad.

6. The method of claim 1, wherein at least a pair of the laser diode regions formed on adjacent ones of the transferred epitaxial mesa dice regions are electrically connected in series via a metal interconnect region or a metal contact region.

7. The method of claim 1, wherein at least a pair of the laser diode regions formed on adjacent ones of the transferred epitaxial mesa dice regions are electrically connected in parallel via a metal interconnect region or a metal contact region.

8. The method of claim 1, wherein each of the bonded epitaxial mesa dice regions are configured to a bonding pad on the carrier wafer;

whereupon the carrier wafer has a larger diameter than the substrate member;

whereupon a bond between each of the bonded epitaxial mesa dice regions and the bonding pad is at least one of metal-metal pairs, oxide-oxide pairs, spin-on-glass, soldering alloys, polymers, photoresists, or wax, and wherein a portion of the release material remains intact after the release.

9. The method of claim 1, wherein the epitaxial material is gallium and nitrogen containing and grown on a polar, non-polar, or semi-polar plane.

10. The method of claim 1, wherein the epitaxial material comprises at least one of GaN, AlN, InN, InGaN, AlGaN, InAlN, InAlGaN, AlAs, GaAs, GaP, InP, AlP, AlGaAs, AlInAs, InGaAs, AlGaP, AlInP, InGaP, AlInGaP, AlInGaAs, or AlInGaAsP;

wherein the energy source comprises a selective etching process to fully or partially remove the release material.

11. The method of claim 10, wherein the epitaxial material comprises at least one of GaN, AlN, InN, InGaN, AlGaN, InAlN, InAlGaN;

wherein the energy source comprises a bandgap selective photoelectricalchemical (PEC) etching process.

12. The method of claim 10, wherein the epitaxial material comprises at least one of AlAs, GaAs, GaP, InP, AlP, AlGaAs, AlInAs, InGaAs, AlGaP, AlInP, InGaP, AlInGaP, AlInGaAs, or AlInGaAsP;

wherein the energy source comprises a selective etching process using a compositionally selective wet etching.

13. The method of claim 12, wherein the release material is comprises at least one of AlGaAs, InGaAs, InGaAP, GaAs, InAlAs, InGaAlAs, InP, AlSb, GaAsSb, AlInP, AlInGaAs, AlInGaP or AlInGaAsP;

whereupon the selective etching process uses at least one of HF, HF;

H₂O, HCl;

H₂O, NH₄OH;

H₂O₂, succinic acid;

NH₄OH, C₆H₆O₇;

H₂O₂;

H₂O or HF;

H₂OO₂;

H₂O.

14. The method of claim 10, wherein the selective etching process selectively removes substantially all of the release material while leaving intact a portion to provide structure before the bonding, and the portion is configured to separate after the bonding.

15. The method of claim 10, wherein the selective etching process selectively removes the release material while leaving an anchor region in tact to provide support before the bonding, and the anchor region is configured to separate after the bonding.

16. The method of claim 10 further comprising forming a metal material overlying the plurality of epitaxial mesa dice regions, while leaving exposed one or more anchor regions, which are configured to selectively break and separate after the bonding.

17. The method of claim 1, wherein each of the laser diode regions comprising a pair of facets configured from a cleaving process or an etching process, the etching process being selected from inductively coupled plasma etching, chemical assisted ion beam etching, or reactive ion beam etching.

18. The method of claim 1, wherein the substrate member is reclaimed and prepared for reuse after transferring each of the bonded epitaxial mesa dice regions to the carrier wafer.

19. The method of claim 1, wherein the carrier wafer comprises at least one of silicon carbide, aluminum nitride, diamond, sapphire, gallium arsenide, indium phosphide, silicon, beryllium oxide, gold, silver, copper, or graphite, carbon nanotubes or graphene or composites thereof.

20. The method of claim 1, wherein the multi-emitter laser diode device is configured as a laser bar having the multi-laser diode.

21. The method of claim 1, wherein the substrate member is a gallium and nitrogen containing substrate such as a GaN substrate and the epitaxial material comprises gallium and nitrogen containing epitaxial layers;

wherein the multi-emitter laser diode device emits in the 350 to 450 nm range or in the 450 to 550 nm range.

22. The method of claim 1, wherein the substrate member is a gallium and arsenic containing substrate such as a GaAs substrate and the epitaxial material comprises gallium and arsenic containing epitaxial layers;

wherein the multi-emitter laser diode device emits in the 600 to 700 nm range, or in the 700 to 800 nm range, or in the 800 to 900 nm range, or in the 900 to 1000 nm range, or in the 1000 to 1100 nm range.

23. The method of claim 1, wherein the substrate member is an indium and phosphorous containing substrate such as an InP substrate and the epitaxial material comprises indium and phosphorous containing epitaxial layers;

wherein the multi-emitter laser diode device emits in the 1100 to 1300 nm range, or in the 1300 to 1400 nm range, or in the 1500 to 1600 nm range.

24. The method of claim 1, wherein the multi-emitter laser diode device is configured with an optical combiner to combine the optical output of the multi-emitters.

25. The method of claim 1, wherein the multi-emitter laser diode device is configured with collimating optics to collimate the output beams from the multi-emitters;

wherein the collimating optics comprise a common fast axis collimating lens and/or a common slow axis collimating lens to collimate the multiple emitted beams.

26. The method of claim 1, wherein the multi-emitter laser diode device is configured with collimating optics to collimate the output beams from the multi-emitters;

wherein the collimating optics comprise a lens array.