Microsoft Corporation
PHOTODIODE ASSEMBLY

Abstract:

A photodiode assembly comprises a photoconductive substrate, including a P-doped region coupled with a controllable voltage biasing source, and an adjacent N-doped well. The photodiode assembly further comprises first and second capacitors coupled with the photoconductive substrate on first and second sides of the N-doped well. First and second control inputs are also coupled with the photoconductive substrate, wherein activation of the first control input causes electrons to flow through a first multiplication region of the N-doped well toward the first capacitor in response to photons striking the photoconductive substrate, and activation of the second control input causes electrons to flow through a second multiplication region of the N-doped well toward the second capacitor in response to photons striking the photoconductive substrate. Selectively controlling a voltage provided by the voltage biasing source changes a multiplication effect provided by the first and second multiplication regions of the N-doped well.