| 摘要 |
1. A photodiode with separated absorption and avalanche zones, comprising a substrate (1) on which a first metallisation (5) constituting an electric contact is deposited, and a heterostructure constituted by a light absorbing layer (2) made of a material having a small forbidden band, and by a first layer (9) which supports a second layer (10), these two layers being made from a material having a large forbidden band, the assembly constituted by the substrate (1) and the layers of the heterostructure (2, 9, 10) being of a first conductivity type and constituting a junction with a layer (11) of a second conductivity type bearing a second contact metallisation (6), the second layer (10) of a large forbidden band, called avalanche layer, having a great thickness (x2 ) and a low doping rate (n2 ), these two characteristics being further linked by the relation n2 . x2 <1,3 . 10**12 at.cm**-2 in such a way that the avalanche phenomenon, enclosed in the second layer (10) develops on a great length but under a low electric field variation rate, the first layer (9) of a large forbidden band being less thick (x1 ) but doped at a higher rate (n1 ) than the avalanche layer (10), these two characteristics being further linked by the relation n1 . x1 apprch= 2,5 . 10**12 at.cm**-2 , this first layer (9) constituting a layer for lowering the electric field. |
