Electron-beam Controlled Switching With Wide Bandgap Semiconductors

Wide bandgap semiconductors are discussed as materials for electron-beam controlled semiconductor switches. Based on a figure of merit which allows to compare materials with different carrier mobility, dielectric strength, and ionization energy, gallium arsenide (GaAs), zinc selenide (ZnSe) and diamond are identified as the most promising materials for high-power electron-beam switching. A mathematical model is presented which allows the calculation of both the steady-state current voltage characteristics and the transient response of these switches to an electron-beam. The results of the simulation and switching experiments with GaAs, ZnSe, and diamond indicate that an electron-beam switching of wide bandgap semiconductors offers and attractive alternative to conventional photoconductive switching.