ION BEAM TREATMENT FOR THE STRUCTURAL INTEGRITY OF AIR-GAP III-NITRIDE DEVICES PRODUCED BY THE PHOTOELECTROCHEMICAL (PEC) ETCHING

• US 20080182420A1
• Filed: 11/15/2007
• Published: 07/31/2008
• Est. Priority Date: 11/15/2006
• Status: Abandoned Application

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Choi, Yong Seok, Wang, Chiou-Fu, Sharma, Rajat, Nakamura, Shuji, Hu, Evelyn L.
• Application Number:
  US11/940,876
• Publication Number:
  US 20080182420A1
• Time in Patent Office: Days
• US Class Current: 438/712
• 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 33/10 with a light reflecting structure, e.g. semiconductor Bragg reflector

Abstract

A method for ensuring the structural integrity of III-nitride opto-electronic or opto-mechanical air-gap nano-structured devices, comprising (a) performing ion beam implantation in a region of the III-nitride opto-electronic and opto-mechanical air-gap nano-structured device, wherein the milling significantly locally modifies a material property in the region to provide the structural integrity; and (b) performing a band-gap selective photo-electro-chemical (PEC) etch on the III-nitride opto-electronic and opto-mechanical air-gap nano-structured device. The method can be used to fabricate distributed Bragg reflectors or photonic crystals, for example. The method also comprises the suitable design of distributed Bragg reflector (DBR) structures for the PEC etching and the ion-beam treatment, the suitable design of photonic crystal distributed Bragg reflector (PCDBR) structures for PEC etching and the ion-beam treatment, the suitable placement of protection layers to prevent the ion-beam damage to optical activity and PEC etch selectivity, and a suitable annealing treatment for curing the material quality after the ion-beam treatment.

Claims

1. A method for enhancing structural integrity of a III-nitride opto-electronic or opto-mechanical air-gap nano-structured device, comprising:

(a) performing an ion beam treatment in a region of the III-nitride opto-electronic or opto-mechanical air-gap nano-structured device, wherein the ion beam treatment locally modifies a material property in the region by making the region resistant to photoelectrochemical (PEC) etching, thereby enhancing the structural integrity; and

(b) performing a band-gap selective PEC etch on the III-nitride opto-electronic or opto-mechanical air-gap nano-structured device, wherein the region is not significantly etched because of the ion beam treatment.

2. The method of claim 1, wherein the ion beam treatment is a focused-ion-beam (FIB) milling.

3. The method of claim 1, wherein the regions comprise supporting struts that enhance the structural integrity of undercut structures of the III-nitride opto-electronic or opto-mechanical air-gap nano-structured device.

4. The method of claim 1, wherein the regions comprise ion-damaged regions.

5. The method of claim 1, wherein the III-nitride opto-electronic or opto-mechanical air-gap nano-structured device is suitably designed for the PEC etching and the ion beam treatment.

6. The method of claim 1, wherein the performing step (b) comprises performing a band-gap selective PEC etch using illumination.

7. The method of claim 1, wherein the performing steps (a) and (b) are used to fabricate an air-gap III-nitride distributed Bragg reflector.

8. The method of claim 7, wherein the III-nitride opto-electronic device is a light emitting diode (LED) including the distributed Bragg reflector.

9. The method of claim 1, wherein the III-nitride opto-electronic device is a light emitting diode (LED) including a two dimensional (2D) photonic crystal (PC).

10. The method of claim 1, further comprising placing a protection layer in selected areas of the III-nitride opto-electronic or opto-mechanical air-gap nano-structured device to prevent the ion beam treatment from damaging optical activity and PEC etch selectivity.

11. The method of claim 1, further comprising annealing the III-nitride opto-electronic or opto-mechanical air-gap nano-structured device for curing material quality after the ion beam treatment.

12. A III-nitride opto-electronic or opto-mechanical air-gap nano-structured device fabricated by the method of claim 1.

13. A method for enhancing structural integrity of a III-nitride opto-electronic or opto-mechanical air-gap nano-structured device, comprising:

(a) performing an ion beam treatment in a region of the III-nitride opto-electronic or opto-mechanical air-gap nano-structured device, wherein the ion beam treatment locally modifies a material property in the region, thereby enhancing the structural integrity; and