Method of manufacture for an ultraviolet laser diode

• US 10,720,757 B1
• Filed: 12/12/2018
• Issued: 07/21/2020
• Est. Priority Date: 11/06/2014
• Status: Active Grant

• Current Assignee: Kyocera SLD Laser Incorporated (Kyocera Corporation)
• Original Assignee: Soraa Laser Diode, Inc. (Kyocera Corporation)
• Inventors: Raring, James W., McLaurin, Melvin, Rudy, Paul, Hsu, Po Shan, Sztein, Alexander
• Primary Examiner(s): Rodriguez, Armando
• Application Number:
  US16/217,359
• Time in Patent Office: 587 Days
• CPC Class Codes: H01S 2301/173 The laser chip comprising special buffer layers, e.g. dislocation prevention or reduction
• CPC Class Codes: H01S 2302/00 Amplification / lasing wavelength
• CPC Class Codes: H01S 5/0206 Substrates, e.g. growth, shape, material, removal or bonding; specific crystal orientation H01S5/3202
• CPC Class Codes: H01S 5/021 Silicon based substrates
• CPC Class Codes: H01S 5/0213 Sapphire, quartz or diamond based substrates
• 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 5/0234 Up-side down mountings, e.g. Flip-chip, epi-side down mountings or junction down mountings
• CPC Class Codes: H01S 5/0425 Electrodes, e.g. characterised by the structure
• CPC Class Codes: H01S 5/04253 having specific optical properties, e.g. transparent electrodes
• CPC Class Codes: H01S 5/04254 characterised by the shape
• CPC Class Codes: H01S 5/2009 by using electron barrier layers
• CPC Class Codes: H01S 5/2031 characterized by special waveguide layers, e.g. asymmetric waveguide layers or defined bandgap discontinuities
• CPC Class Codes: H01S 5/22 having a ridge or stripe structure
• CPC Class Codes: H01S 5/2214 based on oxides or nitrides
• CPC Class Codes: H01S 5/222 having a refractive index lower than that of the cladding layers or outer guiding layers
• CPC Class Codes: H01S 5/30 Structure or shape of the active region; Materials used for the active region
• CPC Class Codes: H01S 5/32308 emitting light at a wavelength less than 900 nm
• CPC Class Codes: H01S 5/34333 : with a well layer based on Ga(In)N or Ga(In)P, e.g. blue laser

Abstract

A method for fabricating a laser diode device includes providing a gallium and nitrogen containing substrate member comprising a surface region, a release material overlying the surface region, an n-type gallium and nitrogen containing material; an active region overlying the n-type gallium and nitrogen containing material, a p-type gallium and nitrogen containing material; and a first transparent conductive oxide material overlying the p-type gallium and nitrogen containing material, and an interface region overlying the first transparent conductive oxide material. The method includes bonding the interface region to a handle substrate and subjecting the release material to an energy source to initiate release of the gallium and nitrogen containing substrate member.

Claims

1. A UV system for germicidal disinfection treatments, the system comprising:

a package;

an ultraviolet laser diode device disposed in the package, the device operable to emit electromagnetic radiation at a wavelength of less than 380 nm and greater than 200 nm, the device comprising;

a gallium and nitrogen containing substrate member comprising a surface region, a release material overlying the surface region, an n-type aluminum, gallium, and nitrogen containing material;

an active region comprising aluminum, gallium, and nitrogen containing material overlying the n-type aluminum, gallium, and nitrogen containing material, a p-type aluminum, gallium, and nitrogen containing material; and

a first transparent conductive oxide material with a band gap energy of greater than 3.2 eV and less than 7.5 eV overlying the p-type aluminum, gallium, and nitrogen containing material, and an interface region overlying the first transparent conductive oxide material, the gallium and nitrogen containing substrate member being configured by subjecting the release material to an energy source to initiate release of the gallium and nitrogen containing substrate member;

a medium selected from at least one of air, food, or water comprising a microorganism to be killed by the electromagnetic radiation at the wavelength of less than 380 nm and greater than 200 nm.

2. The system of claim 1, wherein the interface region is comprised of metal, a semiconductor or another transparent conductive oxide;

wherein the interface region comprises a contact material; and

wherein the release material is selected from a semiconductor, a metal, or a dielectric.

3. The system of claim 1, wherein the active region comprises a plurality of quantum well regions;

wherein the release material is selected from GaN, InGaN, AlInGaN, or AlGaN.

4. The system of claim 1, wherein the release material is selected from InGaN or AlInGaN.

5. The system of claim 1, further comprising a ridge structure configured with the n-type aluminum, gallium, and nitrogen containing material to form an n-type ridge structure;

a dielectric material overlying the n-type aluminum, gallium, and nitrogen containing material; and

a second transparent conductive oxide material with a band gap energy of greater than 3.2 eV overlying an exposed portion of the n-type aluminum, gallium, and nitrogen containing material or overlying an exposed portion of an n-type gallium and nitrogen containing material overlying the n-type aluminum, gallium, and nitrogen containing material such that active region is configured between the first transparent conductive oxide material and the second transparent conductive oxide material to provide an optical guiding effect within the active region, the ridge structure configured with at least a pair of side wall regions, and a upper surface region configured between the pair of side wall regions.

6. The system of claim 1, further comprising an n-type contact material overlying an exposed portion of the n-type aluminum, gallium, and nitrogen containing material or overlying an exposed portion of an n-type gallium and nitrogen containing material overlying the n-type aluminum, gallium, and nitrogen containing material.

7. The system of claim 1, further comprising an n-type contact region overlying an exposed portion of the n-type aluminum, gallium, and nitrogen containing material or overlying an exposed portion of an n-type gallium and nitrogen containing material overlying the n-type aluminum, gallium, and nitrogen containing material;

a patterned transparent oxide region overlying a portion of the n-type contact region; and

a thickness of metal material overlying the patterned transparent oxide region;

wherein the p-type aluminum, gallium, and nitrogen containing material is configured as a ridge waveguide structure to form a p-type ridge structure; and

wherein the transparent conductive oxide is comprised of gallium oxide.

8. The system of claim 1, further comprising:

a second transparent conductive oxide layer with a band gap energy of greater than 3.2 eV overlying the n-type aluminum, gallium, and nitrogen containing material or overlying an exposed portion of an n-type gallium and nitrogen containing material overlying the n-type aluminum, gallium, and nitrogen containing material such that an active region is configured between the first transparent conductive oxide material and the second transparent conductive oxide layer to provide an optical guiding influence whereupon the second transparent conductive oxide layer is configured as a blanket overlying an underlying surface region;

a ridge structure configured within at least the second transparent conductive oxide layer to form transparent conductive oxide ridge structure;

an contact region to expose a portion of the second transparent oxide layer; and

a metal contact material on the exposed portion of the second transparent conductive oxide layer.

9. The system of claim 1, wherein the interface region comprises a transparent conductive oxide containing at least one of a gallium, indium or zinc material;

and a handle substrate comprises gallium oxide; and

wherein the handle substrate surface and interface region surface are bonded directly.

10. The system of claim 1, further comprising a ridge waveguide region in or overlying the n-type aluminum, gallium, and nitrogen containing material;

a transparent conductive oxide region overlying the n-type aluminum, gallium, and nitrogen containing material;

a metal material overlying the transparent conductive oxide region; and

a handle substrate coupled to the gallium and nitrogen containing substrate member;

wherein the transparent conductive oxide region is comprised of a gallium oxide material;

wherein the handle substrate is selected from a semiconductor, a metal, or a dielectric or combinations thereof.

11. The system of claim 1, further comprising a handle substrate coupled to the gallium and nitrogen containing substrate member;

wherein the handle substrate is selected from a sapphire wafer, silicon carbide wafer, aluminum nitride wafer, silicon wafer, gallium arsenide wafer, or an indium phosphide wafer;

wherein the surface region of the gallium and nitrogen containing substrate is configured in a semipolar, polar, or non-polar orientation.

12. The system of claim 1, wherein the first transparent conductive oxide is comprised of a gallium oxide material.

13. The system of claim 1, further comprising a handle substrate coupled to the gallium and nitrogen containing substrate member;

wherein the handle substrate is a gallium arsenide substrate, indium phosphide, or silicon carbide material.

14. A UV treatment system comprising:

a package; and

a laser diode device disposed in the package, the device operable to emit electromagnetic radiation at a wavelength of less than 380 nm and greater than 200 nm, the device comprising;

a gallium and nitrogen containing substrate member comprising a surface region, a release material overlying the surface region, an n-type aluminum, gallium, and nitrogen containing material;

an active region overlying the n-type aluminum, gallium, and nitrogen containing material, a p-type aluminum, gallium, and nitrogen containing material; and

a first transparent conductive oxide region with an band gap energy of greater than 3.2 eV overlying the p-type aluminum, gallium, and nitrogen containing material, and an interface region overlying the conductive oxide material, the gallium and nitrogen containing substrate member being configured by subjecting the release material to an energy source to initiate release of the gallium and nitrogen containing substrate member; and

a ridge structure, and a second transparent conductive oxide material with an band gap energy of greater than 3.2 eV overlying an exposed portion of the n-type aluminum, gallium, and nitrogen containing material or overlying an exposed portion of a gallium, and nitrogen containing material overlying the n-type aluminum, gallium, and nitrogen containing material such that active region is configured between the first transparent conductive oxide material and the second conductive oxide material to provide an optical guiding effect within the active region;

a medium selected from at least one of air, food, or water comprising a microorganism to be killed by the electromagnetic radiation at the wavelength of less than 380 nm and greater than 200 nm.

15. The system of claim 14, further comprising a handle substrate coupled to the gallium and nitrogen containing substrate member;

wherein the interface region comprises a contact region of metal, semiconductor, or transparent conductive oxide;

wherein the release material is a semiconductor, a metal, or a dielectric;

wherein the active region comprises a plurality of quantum well regions;

wherein the handle substrate is a semiconductor, a metal, or a dielectric or combinations thereof;

wherein surface region of the gallium and nitrogen containing substrate is configured in a semipolar, polar, or non-polar orientation.

16. The system of claim 14, wherein the first and second transparent conductive oxides are comprised of a gallium oxide material.

17. A system comprising:

a package; and

a laser diode device disposed in the package, the device operable to emit electromagnetic radiation at a wavelength of less than 380 nm and greater than 200 nm, the device comprising;

a gallium and nitrogen containing substrate member comprising a surface region, a release material overlying the surface region, an n-type aluminum, gallium, and nitrogen containing material;

an active region overlying the n-type aluminum, gallium, and nitrogen containing material, a p-type aluminum, gallium, and nitrogen containing material; and

a first transparent conductive oxide layer with an band gap energy of greater than 3.2 eV overlying the p-type gallium and nitrogen containing material, and an interface region overlying the first transparent conductive oxide layer, the gallium and nitrogen containing substrate member configured by subjecting the release material to an energy source to initiate release of the gallium and nitrogen containing substrate member;

a second transparent conductive oxide layer with a band gap energy of greater than 3.2 eV overlying the n-type aluminum, gallium, and nitrogen containing material or overlying an exposed portion of an n-type gallium and nitrogen containing material overlying the n-type aluminum, gallium, and nitrogen containing material such that an active region is configured between the first transparent conductive oxide layer and the second transparent conductive oxide layer to provide an optical guiding influence whereupon the second transparent conductive oxide layer is configured as a blanket overlying an underlying surface region;

a ridge structure configured within at least the second transparent conductive oxide layer to provide a transparent conductive oxide ridge structure;

a contact region that exposes a portion of the second transparent oxide layer; and

a metal contact material on the exposed portion of the second transparent conductive oxide layer;

a medium selected from at least one of air, food, or water comprising a microorganism to be killed by the electromagnetic radiation at the wavelength of less than 380 nm and greater than 200 nm.

18. The system of claim 17, wherein the water is drinking water that is disinfected by the electromagnetic radiation.

19. The system of claim 17, wherein the first and second transparent conductive oxides are comprised of a gallium oxide material.