Semiconductor device

摘要

A PIN diode includes an anode electrode, a P layer, an I layer, an N layer and a cathode electrode. A polysilicon film is formed in a region near the pn junction or n+n junction where the density of carriers implanted in a forward bias state is relatively high, as a predetermined film having a crystal defect serving as a recombination center. The lifetime can thus be controlled precisely.

主权项

1. A semiconductor device comprising:
an anode portion including a first region of a first conductivity type; a cathode portion including a second region of a second conductivity type; an intermediate portion located between said anode portion and said cathode portion and joined to said anode portion and to said cathode portion; a predetermined film having a crystal defect and formed in at least one of a portion on a side of said anode and a portion on a side of said cathode, carriers of a higher density than a density of carriers present around a center in a thickness direction of said intermediate portion in a forward bias state being present in said portions on respective sides of said anode and said cathode, said intermediate portion including
a predetermined substrate, anda third region of the second conductivity type formed on a surface of said substrate to be in contact with the surface of said substrate and joined to said first region; a maximum impurity density of said third region being higher than an impurity density of said predetermined substrate and lower than a maximum impurity density of said anode portion; said first region and said third region being formed of said predetermined film; and said predetermined film being one selected from a group consisting of a polysilicon film and an amorphous silicon film.