Patent ID: 8628988

Claim:
A method of fabricating a semiconductor laser device, the method comprising: forming a semiconductor structure at least part of which is in the form of a mesa structure having a flat top; depositing a passivation layer over the mesa structure; forming a contact opening in the passivation layer on the flat top of the mesa structure; and depositing a metal contact portion, with the deposited metal contact portion contacting the semiconductor structure via the contact opening, wherein the contact opening formed through the passivation layer has a smaller area than the flat top of the mesa structure, and wherein said depositing of a metal contact portion comprises: depositing a layer of titanium so that the layer of titanium is in contact with the semiconductor structure via the contact opening; depositing a layer of platinum on the titanium layer; depositing a first layer of gold on the platinum layer; depositing a layer of chromium on the first gold layer; and depositing a second layer of gold on the chromium layer.