| 摘要 |
PURPOSE:To obtain an element of ultrahigh speed and high responding sensitivity by a method wherein utilizing a semiconductor substrate in which an abrupt change in conductivity from nonconductive state to conductive state takes place on incidence of light which has an energy not less than an impurity level at ultralow temperature one of electrodes which are prepared on both surface is built to be of divided type and light is given on an exposed surface of the substrate between divided electrodes. CONSTITUTION:On front and back surfaces of a single crystal substrate 10 of a P type or N type InP, GaP, GaAs and others which is prepared to have impurity density of about 10<15>/cm<3> and thickness of approximately 100mum an upper electrode 11 and a lower electrode 12 are built by evaporation of Al or other method. In this arrangement an electrode 11 is of divided type which has a spacing of 100-300mum between, and an exposed surface of the substrate is used as an incident surface 10a, and an impedance between electrodes 11 and 12 is chosen to be approximately 50OMEGA, and a power source of not more than 1 volt is connected between them. In this arrangement by the device contained in an ultralow temperature environment such as 20 deg.K and others and by an avalanche effect generated by controlled incident light on the incident surface 10a switching operation of ultrahigh speed is taken place. |
