摘要 |
A method of fabricating low dark current photodiodes is provided. A multi-layer epitaxial structure is provided, wherein a contact epilayer forms the top-most layer of the structure. A diffusion mask is deposited on top of the contact layer, and at least one hole formed therein. Dopant is diffused through the hole and into both the contact epilayer and the underlying epitaxial structure, forming a doped region. A contact mask is then deposited, covering both the diffusion mask and the holes formed therein. The contact mask and contact epilayer are selectively etched, forming contact mesas and exposing portions of the underlying layers. A passivation coating, also serving as an anti-reflective coating and having uniform thickness, is deposited on top of the contact mesa and the exposed portions. Contacts and bond pads are then deposited, forming a complete photodiode.
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