Method for manufacturing gallium and nitrogen bearing laser devices with improved usage of substrate material

• US 10,658,810 B2
• Filed: 11/26/2018
• Issued: 05/19/2020
• 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: Sztein, Alexander, McLaurin, Melvin, Hsu, Po Shan, Raring, James W.
• Primary Examiner(s): Karimy, Timor
• Application Number:
  US16/199,974
• Publication Number:
  US 20190109432A1
• Time in Patent Office: 540 Days
• CPC Class Codes: H01S 5/0202 Cleaving
• CPC Class Codes: H01S 5/0203 Etching
• CPC Class Codes: H01S 5/0205 during growth of the semiconductor body
• CPC Class Codes: H01S 5/0215 Bonding to the substrate
• CPC Class Codes: H01S 5/0217 Removal of the substrate
• CPC Class Codes: H01S 5/0234 Up-side down mountings, e.g. Flip-chip, epi-side down mountings or junction down mountings
• CPC Class Codes: H01S 5/2201 in a specific crystallographic orientation
• CPC Class Codes: H01S 5/3202 grown on specifically orientated substrates, or using orientation dependent growth
• CPC Class Codes: H01S 5/320275 semi-polar orientation
• 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 5/34346 characterised by the materials of the barrier layers

Abstract

A plurality of dies includes a gallium and nitrogen containing substrate having a surface region and an epitaxial material formed overlying the surface region. The epitaxial material includes an n-type cladding region, an active region having at least one active layer overlying the n-type cladding region, and a p-type cladding region overlying the active region. The epitaxial material is patterned to form the plurality of dies on the surface region, the dies corresponding to a laser device. Each of the plurality of dies includes a release region composed of a material with a smaller bandgap than an adjacent epitaxial material. A lateral width of the release region is narrower than a lateral width of immediately adjacent layers above and below the release region to form undercut regions bounding each side of the release region. Each die also includes a passivation region extending along sidewalls of the active region.

Claims

1. A method for manufacturing a gallium and nitrogen containing device, the method comprising:

providing a gallium and nitrogen containing substrate having a surface region;

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

patterning the epitaxial material to form a plurality of dice, each of the dice corresponding to at least one device, characterized by a first pitch between a pair of dice, the first pitch being less than a design width;

transferring at least a portion of the plurality of dice to a carrier wafer such that each pair of transferred dice is configured with a second pitch between each pair of dice, the second pitch being larger than the first pitch and corresponding to the design width, the transferring comprising;

selectively removing at least a portion of a release region of one or more dice while leaving an anchor region intact between the one or more dice and the gallium and nitrogen containing substrate,

selectively bonding the one or more dice to the carrier wafer, and

releasing the one or more dice from the gallium and nitrogen containing substrate by separating the anchor region associated with each of the one or more dice while a portion of the epitaxial material remains bonded to the carrier wafer.

2. The method of claim 1, wherein each die is shaped as a mesa, and each pair of die having the first pitch ranging between 1 μ

m and 10 μ

m or between 10 micron and 50 microns wide or between 50 and 3000 μ

m long; and

the patterning comprising an etching process.

3. The method of claim 1, wherein the second pitch on the carrier wafer is between 100 microns and 200 microns or between 200 microns and 300 microns.

4. The method of claim 1, wherein the second pitch on the carrier wafer is between 2 times and 50 times larger than the first pitch.

5. The method of claim 1, further comprising processing each of the die to form at least one laser device on each die after the transferring or further comprising forming one or multiple laser diode cavities on each die of epitaxial material.

6. The method of claim 1, wherein each pair of dice overlying the carrier wafer is defined by the second pitch;

and further comprising forming one or more components overlying a space defined by the second pitch, the one or more components being selected from a contact region or a bonding pad.

7. The method of claim 1, wherein the carrier wafer is characterized by a conductive material for a contact region or contact regions;

wherein each of the devices is characterized by a wavelength ranging between 200 and 2000 nm; and

wherein each of the device 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.

8. The method of claim 1, further comprising singulating each of the die by separating each pair of die at a space defined by the second pitch;

wherein the epitaxial material contains GaN, AlN, InN, InGaN, AlGaN, InAlN, and/or InAlGaN.

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

10. The method of claim 1, wherein the carrier wafer comprises at least one of silicon, gallium arsenide, sapphire, silicon carbide, diamond, gallium nitride, AlN, indium phosphide, or metallic.

11. The method of claim 1, wherein the selectively bonding comprises bonding each of the one or more dice to a bonding pad on the carrier wafer.

12. The method of claim 1, wherein the transferring is repeated N times to transfer one or more other die to the carrier wafer, where N is an integer between 1 and 50.

13. The method of claim 1, wherein the transferring is repeated N times to transfer one or more other die to the carrier wafer, where N is an integer between 1 and 50 to remove each of the die to be bonded to the carrier wafer;

whereupon the carrier wafer has a larger diameter than a diameter of the gallium and nitrogen containing substrate.

14. The method of claim 1 wherein the transferring is repeated N times to transfer one or more other die to the carrier wafer, where N is an integer between 1 and 50 to remove each of the die to be bonded to the carrier wafer;

whereupon the carrier wafer has a larger diameter than a diameter of the gallium and nitrogen containing substrate;

whereupon bonds between each of the one or more dice and the carrier wafer comprise at least one of metal-metal pairs, oxide-oxide pairs, spin-on-glass, soldering alloys, polymers, photoresists, and/or wax.

15. The method of claim 1, wherein the transferring is repeated N times to transfer one or more other die to the carrier wafer, where N is an integer between 1 and 50 to remove each of the die to be bonded to the carrier wafer;

whereupon the carrier wafer has a larger diameter than a diameter of the gallium and nitrogen containing substrate;

whereupon bonds between each of the one or more dice and the carrier wafer comprise at least one of metal-metal pairs, oxide-oxide pairs, spin-on-glass, soldering alloys, polymers, photoresists, and/or wax; and

wherein the selectively removing uses a bandgap selective photo-electrical-chemical (PEC) etching to remove the portion of the release region.

16. The method of claim 15, wherein the PEC etching selectively removes substantially all of the release region while leaving intact a portion of the release region to provide structure during the selectively bonding, the portion of the release region forming the anchor region.

17. The method of claim 15, wherein the PEC etching selectively removes the release region while leaving the anchor region in tact to support the die during the selective bonding.

18. The method of claim 15, wherein the PEC etching selectively removes the release region while leaving the anchor region intact to support the die during the selective bonding, the anchor region comprising a defect pillar, a static force, or a Van der Waals force.

19. The method of claim 15 further comprising an additional PEC etching process to completely remove remaining portions of the release region on the one or more dice while the one or more dice are bonded to the carrier wafer.

20. The method of claim 15 further comprising forming a metal material overlying the one or more dice before transferring, while leaving exposed one or more anchor regions, which are configured to selectively break and separate from each of the die after selectively bonding.

21. The method of claim 15 wherein each of the one or more dice comprises a passivation region for protection from PEC etching.

22. The method of claim 1, wherein the release region is composed of a material with a smaller bandgap than an adjacent epitaxial layer.

23. The method of claim 1, wherein the release region is composed of InGaN, InN, InAlN, or InAlGaN.

24. The method of claim 1 wherein the selectively removing forms an undercut region within a vicinity of each of the one or more dice to enable selective release of each of the one or more dice.

25. The method of claim 1, wherein each of the die comprises one or more components, the one or more components being selected from at least one of an electrical contact, a current spreading region, an optical cladding region, a laser ridge, a laser ridge passivation, or a pair of facets, either alone or in any combination.

26. The method of claim 1, wherein the gallium and nitrogen containing substrate is reclaimed and prepared for reuse after transferring.