Patent ID: 7948006

Claim:
A photodiode, comprising: a semiconductor substrate; a n-type buffer layer supported on an upper surface of the InP semiconductor substrate; an intrinsic absorption layer on the buffer layer for absorbing light incident on a top surface of the photodiode; a window layer on the absorption layer for transmitting the incident light to the absorption layer; a dielectric layer on the window layer for providing passivation; a circular p-type region extending from a top surface of the window layer into the absorption layer for forming a p-n junction therein; an annular metal contact on the window layer within the periphery of the circular p-type region for making a contact with the p-type region through a contact region; a bond pad on the dielectric layer, remote from the p-type region, for making an external connection to the photodiode; and a metal link connecting the bond pad to the annular metal contact; wherein the contact region comprises an annular section and an expanded section at the intersection of the metal link and the annular metal contact; and wherein the expanded section has an area at least twice that of the annular section of the contact region.