Silicon avalanche photodiode array

An avalanche photodiode array comprising:

• a body of n-type silicon semiconductor material having phosphorus uniformly distributed therein obtained by neutron transmutation doping, whereby the resistivity of said body is about 30-50 ohm-cm, said resistivity throughout at least an active region of said body has a maximum variance of about 0.5%, said body further having a first body surface and a second body surface opposite to said first surface separated by edge surfaces, and a p-n junction between said first and second body surfaces, said second body surface comprising an entrance surface for receiving light image, said edge surfaces being contoured such that cross-sectional area of said body decreases from said first body surface to said second body surface, whereby premature avalanche breakdown is prevented;
• a plurality of signal contacts forming an array disposed on one of said first and second body surfaces;
• and
• electrical contact means for reverse biasing said signal contacts.