Contact for a semiconductor light emitting device
View Patent ↗A semiconductor structure includes a light emitting layer disposed between an n-type region and a p-type region. A p-electrode is disposed on a portion of the p-type region. The p-electrode includes a reflective first material in direct contact with a first portion of the p-type region and a second material in direct contact with a second portion of the p-type region adjacent to the first portion. The first material and second material are formed in planar layers of substantially the same thickness.
1. A method comprising:
growing a semiconductor structure comprising a light emitting layer disposed between an n-type region and a p-type region;
forming a reflective first material on the p-type region;
forming a resist layer on the reflective first material;
patterning the resist layer to form an opening in the resist layer;
removing a portion of the reflective first material corresponding to the opening in the resist layer;
forming a second material on a remaining portion of the resist layer and a portion of the p-type region exposed by removing a portion of the reflective first material; and
removing the remaining portion of the resist layer.
2. The method of claim 1 wherein the first material and second material are substantially the same thickness.
3. The method of claim 1 wherein the first material comprises silver.
4. The method of claim 1 wherein the second material comprises aluminum.
5. The method of claim 1 further comprising forming a third material on the first and second material, wherein the third material is configured to prevent migration of the first material.
6. The method of claim 5 wherein the third material comprises titanium and tungsten.