Patent ID: 7397101

Claim:
A horizontal germanium silicon photodetector integrated on a substrate comprising: a horizontal silicon pin (positive-intrinsic-negative) diode disposed on a substrate comprising: a first positive region comprising p-type doped silicon; a first intrinsic region comprising silicon; and, a first negative region comprising n-type doped silicon; a horizontal germanium pin diode disposed on top of the horizontal silicon pin diode comprising: a second positive region comprising p-type doped germanium substantially aligned with the first positive region; a second intrinsic region comprising germanium substantially aligned with the first intrinsic region; and, a second negative region comprising n-type doped germanium substantially aligned with the first negative region; an anode contact coupled to the first positive region for establishing electrical contact to both the first positive region and to the second positive region through the first positive region; and, a cathode contact coupled to the first negative region for establishing electrical contact to the first negative region and to the second negative region through the first negative region, thereby establishing a germanium on silicon photodetector with silicon contacts.