Laser devices using a semipolar plane

• US 9,166,374 B1
• Filed: 01/23/2015
• Issued: 10/20/2015
• Est. Priority Date: 10/13/2011
• Status: Active Grant

• Current Assignee: Kyocera SLD Laser Incorporated (Kyocera Corporation)
• Original Assignee: Soraa Laser Diode, Inc. (Kyocera Corporation)
• Inventors: Raring, James W., Lin, You-Da, Elsass, Christiane
• Primary Examiner(s): Niu, Xinning
• Assistant Examiner(s): Vu, Vu A
• Application Number:
  US14/604,223
• Time in Patent Office: 270 Days
• Field of Search: 372/45.012
• US Class Current: 1/1
• CPC Class Codes: H01L 21/0274 Photolithographic processes
• CPC Class Codes: H01L 21/042 Changing their shape, e.g. forming recesses etching of the semiconductor body H01L21/302
• CPC Class Codes: H01L 21/28123 Lithography-related aspects, e.g. sub-lithography lengths; Isolation-related aspects, e.g. to solve problems arising at the crossing with the side of the device isolation; Planarisation aspects
• CPC Class Codes: H01L 21/302 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
• CPC Class Codes: H01L 21/311 Etching the insulating layers by chemical or physical means H01L21/31058 takes precedence
• CPC Class Codes: H01L 21/461 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
• CPC Class Codes: H01L 21/469 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques encapsulating layers H01L21/56; After-treatment of these layers
• CPC Class Codes: H01L 21/4828 Etching etching for cleaning without patterning H01L21/4835
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/16 with a particular crystal structure or orientation, e.g. polycrystalline, amorphous or porous
• CPC Class Codes: H01S 2301/176 Specific passivation layers on surfaces other than the emission facet
• CPC Class Codes: H01S 5/0014 Measuring characteristics or properties thereof measuring techniques per se G01J, G01K, G01N, G01R
• CPC Class Codes: H01S 5/028 Coatings ; Treatment of the laser facets, e.g. etching, passivation layers or reflecting layers
• CPC Class Codes: H01S 5/0287 Facet reflectivity
• CPC Class Codes: H01S 5/04252 characterised by the material
• 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 5/2201 in a specific crystallographic orientation
• CPC Class Codes: H01S 5/2214 based on oxides or nitrides
• CPC Class Codes: H01S 5/320275 : semi-polar orientation
• CPC Class Codes: H01S 5/3214 : comprising materials from other groups of the periodic system than the materials of the active layer, e.g. ZnSe claddings and GaAs active layer
• CPC Class Codes: H01S 5/3216 : quantum well or superlattice cladding layers
• CPC Class Codes: H01S 5/3401 : having no PN junction, e.g. unipolar lasers, intersubband lasers, quantum cascade lasers
• 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: H10N 30/082 : by etching, e.g. lithography

Abstract

An optical device includes a gallium and nitrogen containing substrate comprising a surface region configured in a (20-2-1) orientation, a (30-3-1) orientation, or a (30-31) orientation, within +/−10 degrees toward c-plane and/or a-plane from the orientation. Optical devices having quantum well regions overly the surface region are also disclosed.

Claims

1. A display apparatus comprising:

a housing having an aperture;

an input interface for receiving one or more frames of images;

an optical device comprising;

a gallium and nitrogen containing material comprising a semipolar surface configured on a (30-3-2) orientation, the semipolar surface having an offcut of the orientation;

an n-type region overlying the semipolar surface;

a separate confinement heterostructure (SCH) region overlying the semipolar surface;

an active region comprising at least one light emitting active layer region overlying the n-type region;

the light emitting active layer region comprising a quantum well region or a double hetero-structure region; and

a p-type region overlying the active region;

wherein the active region is configured with the semipolar surface to emit electromagnetic radiation with a wavelength between 400 nm and 500 nm or between 500 nm and 660 nm; and

a wavelength conversion material coupled to the optical device;

a power source electrically coupled to the optical device.

2. The apparatus of claim 1, wherein the offcut of the orientation is between +/−

5 degrees toward a c-plane and between +/−

10 degrees toward an a-plane; and

wherein the active region comprises a plurality of quantum well regions comprising 1 to 7 quantum wells, each of the quantum wells comprising substantially InGaN;

the plurality of quantum well regions ranging in thickness from 2 nm to 5 nm or from 5 nm to 10 nm.

3. The apparatus of claim 1, wherein the active region comprises a double heterostructure region;

the double heterostructure region ranging in thickness from about 10 nm to about 25 nm.

4. The apparatus of claim 1, further comprising an electron blocking layer (EBL) overlying the active region;

the EBL comprising AlGaN, AlInN, or AlInGaN, ranging in thickness from 5 nm to 35 nm, and containing a mole fraction of AlN ranging from 5% to 25%.

5. The apparatus of claim 1, wherein the SCH region comprises InGaN, which comprises an InN mole fraction ranging from 3% to 15% and a thickness ranging from 30 nm to 200 nm.

6. A display apparatus comprising:

a housing having an aperture;

an input interface for receiving one or more frames of images;

an optical device comprising;

a gallium and nitrogen containing material comprising a semipolar surface configured on a (30-3-2) orientation, the semipolar surface having an offcut of the orientation;

an n-type region overlying the semipolar surface;

a superlattice region overlying the semipolar surface, the superlattice region being characterized by 20 to 150 periods of alternating GaN and InGaN layers, alternating AlGaN and InAlGaN layers, alternating AlGaN and GaN layers, or alternating GaN and InAlAGaN layers, each of the alternating layers in the superlattice region having a thickness ranging from 0.5 nm to 20 nm;

an active region comprising at least one light emitting active layer region overlying the superlattice region;

the light emitting active layer region comprising a quantum well region or a double hetero-structure region; and

a p-type region overlying the active region;

wherein the active region is configured to emit electromagnetic radiation with a wavelength between 400 nm and 500 nm or between 500 nm and 660 nm; and

a wavelength conversion material coupled to the optical device;

a power source electrically coupled to the optical device.

7. The apparatus of claim 6, wherein the offcut of the orientation is between +/−

5 degrees toward a c-plane and between +/−

10 degrees toward an a-plane.

8. The apparatus of claim 6, wherein the active region comprises a plurality of quantum well regions comprising 1 to 7 quantum wells, each of the quantum wells comprising substantially InGaN;

the plurality of quantum well regions ranging in thickness from 2 nm to 5 nm or from 5 nm to 10 nm;

or wherein the active region comprises a double heterostructure region, the double heterostructure region ranging in thickness from about 10 nm to about 25 nm; and

wherein the superlattice region is characterized by an n-type dopant.

9. A display apparatus comprising:

a housing having an aperture;

an input interface for receiving one or more frames of images;

a laser device comprising;

a gallium and nitrogen containing material comprising a semipolar surface configured on a (30-3-1) orientation, a (30-31) orientation, a (20-2-1) orientation, or a (30-3-2) orientation, the semipolar surface having an offcut of the orientation;

an n-type cladding region overlying the semipolar surface;

an active region comprising at least one light emitting active layer region overlying the n-type cladding region;

the light emitting active layer region comprising a quantum well region or a double hetero-structure region; and

a p-type cladding region overlying the active region;

a conductive oxide overlying the p-type cladding region;

a laser stripe region comprising at least a portion of the p-type cladding region and the conductive oxide, the laser stripe region being characterized by a cavity orientation substantially parallel to the projection of a c-direction, the laser stripe region having a first end and a second end;

a first etched facet provided on the first end of the laser stripe region; and

a second etched facet provided on the second end of the laser stripe region;

a power source electrically coupled to the laser device;

wherein the laser device is configured to emit electromagnetic radiation with a peak wavelength of between 400 nm and 500 nm or between 500 nm and 560 nm.

10. The apparatus of claim 9, wherein the offcut of the orientation is between +/−

5 degrees toward a c-plane and between +/−

10 degrees toward an a-plane; and

wherein the active region contains a plurality of quantum well regions comprising 1 to 7 quantum wells, each of the quantum wells comprising substantially InGaN;

the plurality of quantum well regions ranging in thickness from 2 nm to 5 nm or from 5 nm to 10 nm;

or wherein the active region contains a double heterostructure region;

the double heterostructure region ranging in thickness from 10 nm to about 25 nm.

11. A display apparatus comprising:

a housing having an aperture;

an input interface for receiving one or more frames of images;

a green laser device comprising;

a gallium and nitrogen containing material comprising a semipolar surface configured on a (30-3-1) orientation, a (30-31) orientation, a (20-2-1) orientation, a (20-21) orientation, or a (30-3-2) orientation, the semipolar surface having an offcut of the orientation;

an n-type cladding region overlying the semipolar surface;

an active region comprising at least one light emitting active layer region overlying the n-type cladding region;

the light emitting active layer region comprising a quantum well region or a double hetero-structure region; and

a laser stripe region overlying the active region, the laser stripe region comprising conductive oxide and being characterized by a cavity orientation substantially parallel to the projection of a c-direction, the laser stripe region having a first end and a second end;

a first etched facet provided on the first end of the laser stripe region; and

a second etched facet provided on the second end of the laser stripe region;

a power source electrically coupled to the green laser device;

wherein the green laser device is configured to emit electromagnetic radiation with a peak wavelength of between 500 nm and 580 nm.

12. The apparatus of claim 11, wherein the offcut of the orientation is between +/−

5 degrees toward a c-plane and between +/−

10 degrees toward an a-plane;

wherein the active region contains a plurality of quantum well regions comprising 1 to 7 quantum wells, each of the quantum wells comprising substantially InGaN;

the plurality of quantum well regions ranging in thickness from 2 nm to 5 nm or from 5 nm to 10 nm;

or wherein the active region contains a double heterostructure region;

the double heterostructure region ranging in thickness from about 10 nm to about 25 nm; and

wherein the first etched facet and the second etched facet are formed using a lithography and etching process.

13. The apparatus of claim 11, wherein the conductive oxide comprises at least one of indium tin oxide (ITO) or zinc oxide (ZnO).

14. The apparatus of claim 11, comprising a p-type gallium and nitrogen containing layer overlying the active region and underlying the conductive oxide region.

15. A display apparatus comprising:

a housing having an aperture;

an input interface for receiving one or more frames of images;

a green laser device comprising;

a gallium and nitrogen containing material comprising a semipolar surface configured on a (30-3-2) orientation, the semipolar surface having an offcut of the orientation;

an n-type cladding region overlying the semipolar surface;

an active region comprising at least one light emitting active layer region overlying the n-type cladding region;

the light emitting active layer comprising a quantum well region or a double hetero-structure region; and

a p-type cladding region overlying the active region, the p-type cladding region being formed from a low temperature GaN, AlInGaN, or AlGaN material;

a laser stripe region formed overlying a portion of the semipolar surface, the laser stripe region being characterized by a cavity orientation substantially parallel to the projection of a c-direction, the laser stripe region having a first end and a second end;

a first etched facet provided on the first end of the laser stripe region; and

a second etched facet provided on the second end of the laser stripe region;

a power source electrically coupled to the green laser device;

wherein the green laser device is configured to emit electromagnetic radiation with a peak wavelength between 500 nm and 580 nm.

16. The apparatus of claim 15, wherein the offcut of the orientation is between +/−

5 degrees toward a c-plane and between +/−

10 degrees toward an a-plane.

17. The apparatus of claim 15, wherein the active region comprises a plurality of quantum well regions comprising 1 to 7 quantum wells, each of the quantum wells comprising substantially InGaN;

the plurality of quantum well regions ranging in thickness from 2 nm to 5 nm or from 5 nm to 10 nm;

or wherein the active region comprises a double heterostructure region; and

wherein the double heterostructure region ranging in thickness from 10 nm to about 25 nm.

18. A display apparatus comprising:

a housing having an aperture;

an input interface for receiving one or more frames of images;

a laser device comprising;

a gallium and nitrogen containing material comprising a semipolar surface configured on a (30-31) orientation, a (30-31) orientation, a (20-2-1) orientation, a (20-21) orientation, or a (30-3-2) orientation, the semipolar surface having an offcut of the orientation, the offcut of the orientation characterized by an offcut toward an a-plane;

the offcut toward the a-plane being greater in magnitude than 1 degree and less than about 12 degrees;

an n-type cladding region overlying the semipolar surface;

an active region comprising at least one light emitting active layer region overlying the n-type cladding region;

the light emitting active layer region comprising a quantum well region or a double hetero-structure region; and

a p-type cladding region overlying the active region;

a laser stripe region overlying a portion of the semipolar surface, the laser stripe region being characterized by a cavity orientation substantially parallel to the projection of a c-direction, the laser stripe region having a first end and a second end;

a first facet provided on the first end of the laser stripe region;

a second facet provided on the second end of the laser stripe region; and

a power source electrically coupled to the laser device;

wherein the laser device is configured to emit an electromagnetic radiation with a peak wavelength of between 400 nm and 500 nm or between 500 nm and 580 nm.

19. The apparatus of claim 18, wherein the offcut toward the a-plane is characterized by the absolute magnitude of angle between 3 and 10 degrees.

20. The apparatus of claim 18, wherein the offcut of the orientation is characterized by an offcut toward a c-plan of between +/−

5 degrees.