LATERAL ELECTROCHEMICAL ETCHING OF III-NITRIDE MATERIALS FOR MICROFABRICATION

• US 20170133826A1
• Filed: 01/26/2017
• Published: 05/11/2017
• Est. Priority Date: 06/28/2012
• Status: Abandoned Application

• Current Assignee: Yale University
• Original Assignee: Yale University
• Inventors: HAN, JUNG
• Application Number:
  US15/416,134
• Publication Number:
  US 20170133826A1
• Time in Patent Office: Days
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01L 21/306 Chemical or electrical treatment, e.g. electrolytic etching to form insulating layers H01L21/31
• CPC Class Codes: H01L 21/30612 Etching of AIIIBV compounds
• CPC Class Codes: H01L 21/30635 of AIIIBV compounds
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• CPC Class Codes: H01L 33/105 with a resonant cavity structure
• CPC Class Codes: H01S 5/18341 Intra-cavity contacts
• CPC Class Codes: H01S 5/18363 comprising air layers
• CPC Class Codes: H01S 5/18369 based on dielectric materials
• CPC Class Codes: H01S 5/187 using Bragg reflection
• CPC Class Codes: H01S 5/343 in AIIIBV compounds, e.g. AlGaAs-laser , InP-based laser
• CPC Class Codes: H01S 5/34333 with a well layer based on Ga(In)N or Ga(In)P, e.g. blue laser

Abstract

Conductivity-selective lateral etching of III-nitride materials is described. Methods and structures for making vertical cavity surface emitting lasers with distributed Bragg reflectors via electrochemical etching are described. Layer-selective, lateral electrochemical etching of multi-layer stacks is employed to form semiconductor/air DBR structures adjacent active multiple quantum well regions of the lasers. The electrochemical etching techniques are suitable for high-volume production of lasers and other III-nitride devices, such as lasers, HEMT transistors, power transistors, MEMs structures, and LEDs.

Claims

1. A III-nitride DBR device comprising:

a multi-layer structure having first and second layers formed of III-nitride material, wherein a conductivity of the first layers is different from a conductivity of the second layers;

a MQW structure formed adjacent the multi-layer structure, wherein the MQW structure comprises an active region of the device;

vias formed into the multi-layer structure proximal to the MQW structure; and

regions adjacent the vias in which portions of the second layers have been completely removed to form at least two first layers separated by one or more layers of air.

2. The DBR device of claim 1, wherein the MQW structure forms an active region of a laser.

3. The DBR device of claim 1, wherein the first layers and second layers comprise GaN.

4. The DBR device of claim 3, wherein the second layers comprise high n-type conductivity material.

5. The DBR device of claim 1, wherein the thicknesses of the first layers are substantially the same.

6. The DBR device of claim 1, wherein the thicknesses of the first layers correspond to approximately one-quarter of a selected emission wavelength for the laser.

7. The DBR device of claim 1, wherein the removed portions of the second layers and remaining first layers form a structure having periodic contrast of optical refractive index.