Tetra-lateral position sensing detector

摘要

The present invention is directed to a position sensing detector made of a photodiode having a semi insulating substrate layer; a buffered layer that is formed directly atop the semi-insulating substrate layer, an absorption layer that is formed directly atop the buffered layer substrate layer, a cap layer that is formed directly atop the absorption layer, a plurality of cathode electrodes electrically coupled to the buffered layer or directly to the cap layer, and at least one anode electrode electrically coupled to a p-type region in the cap layer. The position sensing detector has a photo-response non-uniformity of less than 2% and a position detection error of less than 10 μm across the active area.

主权项

1. A position sensing detector comprising a photodiode having an active area, said photodiode comprising
a semi insulating substrate layer; a buffered layer, wherein said buffered layer is formed directly atop the semi-insulating substrate layer; an absorption layer, wherein said absorption layer is formed directly atop the buffered layer; a cap layer, wherein said cap layer is formed directly atop the absorption layer; four cathode electrodes electrically coupled to said buffered layer, wherein each of said four cathode electrodes is positioned parallel to other of said four cathode electrodes and in opposing corners of the photodiode; and at least one anode electrode electrically coupled to a p-type region in said cap layer, wherein said detector is capable of detecting eye-safe wavelengths, wherein a shunt resistance of the position sensing detector at −10 mV ranges from 1 Megaohms to 8 Megaohms and wherein a capacitance of the position sensing detector at 0 V ranges from 322 picofarads to 900 picofarads.