Large area semiconductor detector with internal gain

An avalanche photodiode array configured to detect incident electromagnetic radiation comprising:

• a plurality of n-wells extending inward from a bottom surface;
• and
• a p-region that is disposed partially around each of the n-wells, wherein substantially at an interface region between each n-well and the p-region of a p-n junction is disposed, wherein the p-region forms a top surface, and the p-region and the n-wells form the bottom surface that is opposite to the top surface, wherein the p-n junction meets the bottom surface at an obtuse angle on the n-wells side of the p-n junction.

An array of position sensitive APDs configured to detect incident electromagnetic radiation comprising:

• a plurality of n-wells extending inward from a bottom surface;
• and
• a p-region that is disposed partially around each of the n-wells, wherein substantially at an interface region between each n-well and the p-region a p-n junction is disposed, wherein the p-region forms a top surface, and the p-region and the n-wells form the bottom surface that is opposite to the top surface, wherein the p-n junction meets the bottom surface at an obtuse angle on the n-wells side of the p-n junction.