Photodetector array having different photodiode structures

摘要

A method of fabricating a photodiode array having different photodiode structures includes providing a semiconductor substrate having first and second diode areas including a bottom substrate portion doped with a first doping type, an intrinsic layer, and a top silicon layer doped with a second doping type. The second diode areas are implanted with the second doping type. A dopant concentration in the surface of the second diode areas is at least three times higher than in the first diode areas. The top silicon layer is thermally oxidized to form a thermal silicon oxide layer to provide a bottom Anti-Reflective Coating (ARC) layer. The second diode areas grow thermal silicon oxide thicker as compared to the first diode areas. A top ARC layer is deposited on the bottom ARC layer. First PDs are provided in the first diode areas and second PDs provided in the second diode areas.

主权项

1. A photodetector array (PDA), comprising:
a semiconductor substrate including first diode areas and second diode areas having a bottom substrate portion doped with a first doping type, an intrinsic layer on said bottom substrate portion, and a top silicon comprising layer doped with a second doping type on said intrinsic layer, said bottom substrate portion providing a bottom diode layer and said top silicon comprising layer providing a top diode layer, wherein a second surface dopant concentration in a surface of said second diode areas that is at least three times higher than a first surface dopant concentration in a surface of said first diode areas; a thermal silicon oxide layer on said top silicon comprising layer which provides a bottom Anti-Reflective Coating (ARC) layer for said first and second diode areas, wherein said second diode areas have said thermal silicon oxide layer thicker as compared to said thermal silicon oxide layer on said first diode areas, and a top ARC layer having a refractive index greater than said thermal silicon oxide layer on said bottom ARC layer, wherein first PDs are provided in said first diode areas and second PDs are provided in said second diode areas.