Method of fabricating optical devices using laser treatment

• US 9,048,170 B2
• Filed: 11/09/2010
• Issued: 06/02/2015
• Est. Priority Date: 11/09/2010
• Status: Active Grant

• Current Assignee: Kyocera SLD Laser Incorporated (Kyocera Corporation)
• Original Assignee: Soraa Laser Diode, Inc. (Kyocera Corporation)
• Inventors: Pfister, Nicholas J., Raring, James W., Schmidt, Mathew
• Primary Examiner(s): Fahmy, Wael
• Assistant Examiner(s): TANG, SUIAN
• Application Number:
  US12/942,817
• Publication Number:
  US 20130234111A1
• Time in Patent Office: 1,666 Days
• Field of Search: 257 12- 14, 257 79-103, 257/918, 257E51018-E51022, 257E33001-E33077, 257/E33.054, 257/E25.028, 257/E25.032, 438/22, 438/29, 438/34, 438/42
• US Class Current: 1/1
• CPC Class Codes: H01L 29/20 including, apart from doping materials or other impurities, only AIIIBV compounds
• CPC Class Codes: H01L 2933/0066 relating to arrangements for conducting electric current to or from the semiconductor body
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01S 5/0014 Measuring characteristics or properties thereof measuring techniques per se G01J, G01K, G01N, G01R
• CPC Class Codes: H01S 5/0202 Cleaving
• CPC Class Codes: H01S 5/0203 Etching
• CPC Class Codes: H01S 5/0421 characterised by the semiconducting contacting layers electrodes H01S5/0425
• CPC Class Codes: H01S 5/2013 MQW barrier reflection layers
• CPC Class Codes: H01S 5/2201 in a specific crystallographic orientation
• CPC Class Codes: H01S 5/3013 AIIIBV compounds
• CPC Class Codes: H01S 5/32025 non-polar orientation
• CPC Class Codes: H01S 5/32341 blue laser based on GaN or GaP

Abstract

A method for forming optical devices. The method includes providing a gallium nitride substrate member having a crystalline surface region and a backside region. The method also includes subjecting the backside region to a laser scribing process to form a plurality of scribe regions on the backside region and forming a metallization material overlying the backside region including the plurality of scribe regions. The method removes at least one optical device using at least one of the scribe regions.

Claims

1. An optical device comprising:

a gallium and nitrogen containing substrate member having a crystalline surface region and a backside opposite the crystalline surface region;

a laser stripe region overlying a portion of the crystalline surface region;

at least one laser scribe line on the backside and underlying at least a portion of the laser stripe region, the at least one laser scribe line comprising a recessed region extending partially through a thickness of the gallium and nitrogen containing substrate, wherein portions of the backside within a vicinity of the at least one laser scribe line have a higher conductivity than portions of the backside outside the vicinity of the at least one laser scribe line; and

a metallization material contacting the backside and one or more portions of the at least one laser scribe line to form a metal contact.

2. The device of claim 1 wherein the metallization material comprises aluminum material.

3. The device of claim 1 wherein the metallization material comprises a gold material.

4. The device of claim 1 wherein the metallization material comprises a gold material and a nickel material.

5. The device of claim 1 wherein the metal contact is an n-type metal contact.

6. The device of claim 1 further comprising an n-type gallium nitride region overlying the crystalline surface region, an active region overlying the n-type gallium nitride region, and the laser stripe region overlying the active region.

7. The device of claim 6 wherein the active region comprises one to twenty quantum well regions, and is characterized by a thickness of 10 Angstroms to about 50 Angstroms.

8. The device of claim 6 wherein the active region comprises one to twenty quantum well regions, and is characterized by a thickness of 50 Angstroms to about 100 Angstroms.

9. The device of claim 6 wherein the active region comprises an electron blocking region.

10. The device of claim 6 wherein the active region comprises a separate confinement hetero-structure.

11. The device of claim 1, wherein the at least one laser scribe line is parallel to the laser stripe region.

12. The device of claim 1, wherein the at least one laser scribe line is 3 μ

m to 5 μ

m deep.

13. The device of claim 1, wherein the metallization material comprises a n-type contact.

14. The device of claim 1, wherein the substrate is a nonpolar or a semipolar substrate.

15. The device of claim 1, wherein the substrate is an m-plane substrate.

16. The device of claim 1, wherein the at least one laser stripe region is substantially parallel to the c-direction.

17. The device of claim 1, wherein the metallization material contacts edges of the at least one laser scribe line.

18. The device of claim 1, wherein the optical device comprises a light emitting diode device.

19. The device of claim 1, wherein the optical device comprises a laser device.

20. The device of claim 1, wherein the crystalline surface region is configured in a non-polar orientation.

21. The device of claim 1, wherein the crystalline surface region is configured in a semi-polar orientation.

22. The device of claim 1, wherein the crystalline surface region is configured in an m-plane orientation having a +/−

6 degree off-cut.

23. The device of claim 1, wherein the crystalline surface region is configured in a {20-21} orientation.

24. The device of claim 1, wherein the at least one laser scribe line comprises multiple laser scribe lines wherein each of the laser scribe lines is arranged in a parallel manner.