Five layer semiconductor device with separate insulated turn-on and turn-off gates

Claim 1

A semiconductor device comprising: a first layer of p-type conductivity; a second layer of n-type conductivity contacting said first layer; a third layer of p-type conductivity contacting said second layer; a fourth layer of n-type conductivity contacting said third layer; a fifth layer of p-type conductivity contacting said fourth layer; an anode electrode formed on said first layer; a cathode electrode formed on said fourth and fifth layers; a first gate electrode insulatively formed over said third layer, forming a first field-effect transistor in cooperation with said second, third and fourth layers and forming a first current channel in the surface of said third layer interposed between said second and fourth layers upon receipt of a turn-on signal, flow of current in said first current channel removing the electrical barrier between said second and third layers and permitting current flow between said anode and cathode electrodes, and a second gate electrode insulatively formed over said fourth layer, forming a second field-effect transistor in cooperation with said third, fourth and fifth layers, whereupon application of a turn-off signal to said second electrode forms a second current channel in the surface of said fourth layer interposed between said third and fifth layers, reestablishing the electrical barrier betwen said second and third layers and blocking said current flow between said anode and cathode electrodes.