Investigation of doping profile effect on characteristics of ion-implanted GaAs MESFET
Ion-implanted GaAs MESFET was modeled and dependence of MESFET characteristics on doping profile parameters was found. Dependence of transistors characteristics on doping profile parameters variation was investigated.
Transport equations for electrons in two-valley semiconductors
Transport equations are derived for particles, momentum, and energy of electrons in a semiconductor with two distinct valleys in the conduction band, such as GaAs. Care is taken to state and discuss the assumptions which are made in the derivation. The collision processes are expressed in terms of relaxation times. The accuracy is improved by considering these to depend on the average kinetic energy rather than the electron temperature. Other transport equations used in the literature are discussed, and shown to be incomplete and inaccurate in many cases. In particular, the usual assumption that the mobility and diffusion constant depend locally on the electric field strength is shown to be incorrect. Rather, these quantities should be taken as functions of the local average velocity of electrons in the lower valley.
HIGH-FREQUENCY CONDUCTIVITY, CARRIER WAVES, AND ACOUSTIC AMPLIFICATION IN DRIFTED SEMICONDUCTOR PLASMAS.
Abstract : The temperature modulation of charge carriers in a semiconductor is analyzed for a plane wave propagating along a static electric field. The effect of temperature modulation on the rf conductivity is considered. A phenomenological description of energy relaxation, momentum relaxation and intercarrier collisions is used. The expression for conductivity is used to derive a dispersion relation for carrier waves in drifted semiconductor plasmas. Two new waves are introduced by relaxing the assumption of isothermal carrier transport. The theory is applied to a discussion of acoustic amplification in piezoelectric semiconductors. It is shown that the non-isothermal effects limit the maximum gain which can be achieved at high frequencies. (Author)