Non-polar (Al,B,In,Ga)N quantum well and heterostructure materials and devices

• US 7,982,208 B2
• Filed: 06/21/2006
• Issued: 07/19/2011
• Est. Priority Date: 04/15/2002
• Status: Active Grant

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Keller, Stacia, Craven, Michael D., Denbaars, Steven P., Margalith, Tal, Nakamura, Shuji, Mishra, Umesh K., Speck, James Stephen
• Primary Examiner(s): Nguyen; Thinh T
• Application Number:
  US11/472,033
• Publication Number:
  US 20060278865A1
• Time in Patent Office: 1,854 Days
• Field of Search: 257/11, 257/12, 257/14, 257/19
• US Class Current: 257/14
• CPC Class Codes: C30B 25/02 Epitaxial-layer growth
• CPC Class Codes: C30B 25/04 Pattern deposit, e.g. by using masks
• CPC Class Codes: C30B 25/105 by irradiation or electric discharge
• CPC Class Codes: C30B 25/18 characterised by the substrate
• CPC Class Codes: C30B 29/403 AIII-nitrides
• CPC Class Codes: C30B 29/406 Gallium nitride
• CPC Class Codes: C30B 29/605 Products containing multiple oriented crystallites, e.g. columnar crystallites
• CPC Class Codes: H01L 21/0237 Materials
• CPC Class Codes: H01L 21/0242 Crystalline insulating materials
• CPC Class Codes: H01L 21/02433 Crystal orientation
• CPC Class Codes: H01L 21/02458 Nitrides
• CPC Class Codes: H01L 21/0254 Nitrides
• CPC Class Codes: H01L 21/02609 Crystal orientation
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 21/02639 Preparation of substrate for selective deposition
• CPC Class Codes: H01L 21/02647 Lateral overgrowth

Abstract

A method for forming non-polar (Al,B,In,Ga)N quantum well and heterostructure materials and devices. Non-polar (11 20) a-plane GaN layers are grown on an r-plane (1 102) sapphire substrate using MOCVD. These non-polar (11 20) a-plane GaN layers comprise templates for producing non-polar (Al, B, In, Ga)N quantum well and heterostructure materials and devices.

Claims

1. A nitride semiconductor device comprised of one or more non-polar (Al, B, In, Ga)N layers grown on non-polar GaN, wherein the nitride semiconductor device is created using a process comprising:

(a) growing one or more non-polar (Al, B, In, Ga)N layers on non-polar GaN, wherein the grown non-polar (Al, B, In, Ga)N layers comprise at least one light emitting quantum well structure including alternating layers of different bandgap such that wells are formed in the light emitting quantum well structure'"'"'s energy profile, wherein the alternating layers of different bandgap include at least a quantum barrier layer and at least a quantum well layer, the quantum well layer has a thickness that is more than 5 nm and 11 nm or less, and the light emitting quantum well structure'"'"'s peak photoluminescence (PL) emission wavelength and intensity are greater than PL emission wavelength and intensity from a light emitting non-polar (Al, B, In, Ga)N quantum well structure having a quantum well layer with a thickness less than 5 nm.

2. The device of claim 1, further comprising a substrate, wherein the non-polar GaN is grown on the substrate.

3. The device of claim 2, wherein the substrate is sapphire, silicon carbide, gallium nitride, silicon, zinc oxide, boron nitride, lithium aluminate, lithium niobate, germanium, aluminum nitride, or lithium gallate.

4. The device of claim 1, wherein the quantum well layer comprises an Indium-containing quantum well layer.

5. The device of claim 1, wherein the light emitting quantum well structure is capped with GaN.

6. The device of claim 1, wherein the grown non-polar (Al, B, In, Ga)N layers comprise at least one heterostructure.

7. The device of claim 6, wherein the heterostructure is an (Al,Ga)N/GaN heterostructure.

8. The device of claim 1, further comprising growing the non-polar GaN by:

(1) annealing a substrate;

(2) depositing a nitride-based buffer layer on the substrate;

(3) growing the non-polar GaN on the buffer layer; and

(4) cooling the non-polar GaN under a nitrogen overpressure.

9. The device of claim 1, wherein the growing step is performed by a method selected from a group comprising metalorganic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), liquid phase epitaxy (LPE), hydride vapor phase epitaxy (HVPE), sublimation, and plasma-enhanced chemical vapor deposition (PECVD).

17. The device of claim 1, wherein the non-polar GaN is a substrate.

18. The device of claim 1, wherein the peak photoluminescence (PL) emission wavelength and intensity increase with increasing quantum well layer width.

19. The device of claim 1, wherein the light emitting quantum well structure has the photoluminescence (PL) intensity that peaks at an emission wavelength between 380 and 450 nm.

20. The device of claim 1, wherein band profiles for the non-polar (Al, B, In, Ga)N layers are not influenced by polarization-induced electric fields.

25. The device of claim 1, wherein the non-polar GaN is a-plane or m-plane GaN.

10. A nitride semiconductor device, comprising:

(a) one or more non-polar (Al, B, In, Ga)N layers grown on non-polar GaN, wherein the grown non-polar (Al, B, In, Ga)N layers comprise at least one light emitting quantum well structure, including alternating layers of different bandgap such that wells are formed in the light emitting quantum well structure'"'"'s energy profile, wherein the alternating layers of different bandgap include at least a quantum barrier layer and at least a quantum well layer, the quantum well layer has a thickness that is more than 5 nm and 11 nm or less, and the light emitting quantum well structure'"'"'s peak photoluminescence (PL) emission wavelength and intensity are greater than PL emission wavelength and intensity from a light emitting non-polar (Al, B, In, Ga)N quantum well structure having a quantum well layer with a thickness less than 5 nm.

11. The device of claim 10, further comprising a substrate, wherein the non-polar GaN is grown on the substrate.

12. The device of claim 11, wherein the substrate is sapphire, silicon carbide, gallium nitride, silicon, zinc oxide, boron nitride, lithium aluminate, lithium niobate, germanium, aluminum nitride, or lithium gallate.

13. The device of claim 10, wherein the quantum well layer comprises an Indium-containing quantum well layer.

14. The device of claim 10, wherein the light emitting quantum well structure is capped with GaN.

15. The device of claim 10, wherein the non-polar (Al, B, In, Ga)N layers comprise at least one heterostructure.

16. The device of claim 15, wherein the heterostructure is an (Al,Ga)N/GaN heterostructure.

21. The device of claim 10, wherein the non-polar GaN is a substrate.

22. The device of claim 10, wherein the peak photoluminescence (PL) emission wavelength and intensity increase with increasing quantum well layer width.

23. The device of claim 10, wherein the light emitting quantum well structure has the photoluminescence (PL) intensity that peaks at an emission wavelength between 380 and 450 nm.

24. The device of claim 10, wherein band profiles for the non-polar (Al, B, In, Ga)N layers are not influenced by polarization-induced electric fields.

26. The device of claim 10, wherein the non-polar GaN is a-plane or m-plane GaN.