FABRICATING A GALLIUM NITRIDE DEVICE WITH A DIAMOND LAYER

• US 20100155900A1
• Filed: 12/22/2008
• Published: 06/24/2010
• Est. Priority Date: 12/22/2008
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Bernstein, Steven D., Korenstein, Ralph, Pereira, Stephen J.
• Granted Patent: US 7,989,261 B2
• Time in Patent Office: Days
• US Class Current: 257/615
• CPC Class Codes: H01L 21/02389 Nitrides
• CPC Class Codes: H01L 21/02527 Carbon, e.g. diamond-like carbon
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 29/1602 Diamond
• CPC Class Codes: H01L 29/2003 Nitride compounds
• CPC Class Codes: H01L 29/267 in different semiconductor regions , e.g. heterojunctions H01L29/263 takes precedence
• CPC Class Codes: H01L 29/66431 with a heterojunction interface channel or gate, e.g. HFET, HIGFET, SISFET, HJFET, HEMT with an active layer made of a group 13/15 material H01L29/66462
• CPC Class Codes: H01L 29/66462 with a heterojunction interface channel or gate, e.g. HFET, HIGFET, SISFET, HJFET, HEMT
• CPC Class Codes: H01L 29/7786 with direct single heterostructure, i.e. with wide bandgap layer formed on top of active layer, e.g. direct single heterostructure MIS-like HEMT

Abstract

In one aspect, a method includes fabricating a device. The device includes a gallium nitride (GaN) layer, a diamond layer disposed on the GaN layer and a gate structure disposed in contact with the GaN layer and the diamond layer.

In another aspect, a device includes a gallium nitride (GaN) layer, a diamond layer disposed on the GaN layer and a gate structure disposed in contact with the GaN layer and the diamond layer.

Claims

1. A method, comprising:

fabricating a device comprising;

a gallium nitride (GaN) layer;

a diamond layer disposed on the GaN layer; and

a gate structure disposed in contact with the GaN layer and the diamond layer.

2. The method of claim 1 wherein the fabricating further comprises depositing the diamond layer onto the GaN layer.

3. The method of claim 2 wherein the depositing comprises depositing the diamond layer onto the GaN layer using a microwave plasma chemical vapor deposition (CVD.

4. The method of claim 2 wherein the depositing comprises depositing a diamond layer that is greater than 1,000 Angstroms.

5. The method of claim 2 wherein the diamond layer is a first diamond layer,

wherein depositing the first diamond layer further comprises depositing a first diamond layer onto a first surface of the GaN, and

further comprising disposing a second diamond layer onto a second surface of the GaN layer opposite the first surface of the GaN layer.

6. The method of claim 5 wherein disposing a second diamond layer onto a second surface of the GaN layer opposite the first surface of the GaN layer comprises attaching to the second surface of the GaN layer a second diamond layer having a first thermal conductivity and a third diamond layer disposed thereto having a second thermal conductivity greater than the first thermal conductivity.

7. The method of claim 1 wherein fabricating a device comprising the GaN layer comprises fabricating a device comprising a GaN layer comprising at least one of undoped GaN, doped GaN or GaN combined with another element.

8. The method of claim 1 wherein fabricating a device comprises fabricating one of a high frequency device, a high electron mobility transistor (HEMT) or a microwave device.

9. A method comprising:

disposing a diamond layer onto a first surface of gallium nitride (GaN);

removing a portion of the diamond layer exposing the first surface of the GaN; and

forming a gate structure in contact with the first surface of the GaN and the diamond layer.

10. The method of claim 9 wherein the diamond layer is a first diamond layer, and

further comprising attaching a second diamond layer to a second surface of the GaN opposite the first surface of the GaN.

11. The method of claim 9, further comprising fabricating at least one of a high frequency device, a high electron mobility transistor (HEMT) or a microwave device from the diamond/GaN structure.

12. The method of claim 9 wherein removing a portion of the diamond layer exposing the GaN surface comprises removing a portion of the diamond layer using oxygen plasma.

13. The method of claim 9 wherein disposing a diamond layer comprises depositing a diamond layer.

14. The method of claim 13, further comprising performing an ultrasound on the GaN immersed in a solution comprising nano-diamond particles prior to depositing the diamond layer.

15. The method of claim 9, further comprising:

growing GaN on a first substrate;

disposing a layer of material onto the GaN; and

removing the first substrate.

16. The method of claim 15 wherein growing GaN on a first substrate comprises growing GaN on one of silicon carbide, silicon or sapphire.

17. The method of claim 15 wherein disposing a layer of material onto the GaN comprises disposing one of a silicon layer or a glass layer.

18. The method of claim 15, further comprising removing the layer of material to form a diamond/GaN structure.

19. A device, comprising:

a gallium nitride (GaN) layer;

a diamond layer disposed on the GaN layer; and

a gate structure disposed in contact with the GaN layer and the diamond layer.

20. The device of claim 19 wherein the diamond layer is a first diamond layer,

wherein the gate and the first diamond layer are disposed on a first surface of the GaN layer, and

further comprising a second diamond layer having a first thermal conductivity and disposed on a second surface of the GaN layer opposite the first surface of the GaN.

21. The device of claim 20, further comprising a third diamond layer having a second thermal conductivity greater than the first thermal conductivity and disposed on the second diamond layer.

22. The device of claim 19, further comprising an interlayer disposed between the second diamond layer and the GaN layer.

23. The device of claim 19 wherein the second diamond layer is greater than 2 mils and the first diamond layer less than 1 mil.

24. The device of claim 19 wherein the device is one of a high frequency device, a high electron mobility transistor (HEMT) or a microwave device.

25. The device of claim 19 wherein the GaN layer comprises at least one of undoped GaN, doped GaN or GaN combined with another element.