Conformal metallization process for the fabrication of semiconductor laser devices

摘要

A method of fabricating a semiconductor laser device by forming a semiconductor structure at least part of which is in the form of a mesa structure having a flat top. The steps include 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. The contact opening formed through the passivation layer has a smaller area than the flat top of the mesa structure to allow for wider tolerances in alignment accuracy. The metal contact portion comprises a platinum layer between one or more gold layers to provide an effective barrier against Au diffusion into the semiconductor material.

主权项

1. A semiconductor laser device comprising:
a semiconductor structure at least part of which is in the form of a mesa structure having a flat top; a passivation layer over the mesa structure, the passivation layer defining a contact opening on the flat top of the mesa structure; and a metal contact portion contacting the semiconductor via the contact opening, wherein the contact opening defined by the passivation layer has a smaller area than the flat top of the mesa structure, wherein the metal contact portion comprises at least one layer comprising gold and a layer comprising platinum disposed between said at least one layer comprising gold and said semiconductor structure, and wherein said at least one layer comprising gold comprises a first gold layer and a second gold layer separated by a chromium layer.