Abstract: An electron beam controlled semiconductor switch is capable of carrying large currents without being restricted by the space charge limited current condition. The switch includes a block of semiconductor material having ohmic contacts connectable to first and second electrical conductors. Semi-insulating GaAs may be used as the semiconductor material. A shallow donor or acceptor doped layer may be formed at the surface receiving the electron beam for increased band-edge radiation. This recombination radiation ionizes, together with X-rays produced by Bremsstrahlung, the bulk of the semiconductor block to provide relatively high current density and current gain.

Abstract: A light activated semiconductor switch is capable of carrying large currents without requiring continuous illumination of the semiconductor to sustain conduction. The switch includes a block of semiconductor material having ohmic contacts connectable to first and second electrical conductors and a deep acceptor level between conduction and valence bands that may be counterdoped with shallow donors. The source of light used to switch between the ON and OFF states is an electromagnetic radiation device which directs first and second beams onto the block between the ohmic contacts. The first beam causes photo-excitation of electrons form the deep acceptor level into the conduction band to provide initial electrons for conduction between the first and second electrical conductors. The second beam causes electrons from the conduction band and holes from the deep acceptor level to combine, thereby interrupting conduction between the first and second electrical conductors.