The effect of thermal diffusion on the electrical response of MSM photodetector

The effect of thermal diffusion on electron transport and the response of the photodetector are numerically investigated. A self-adjoint formulation of the Energy transport model of semiconductor devices is used to simulate the electron transport in the photodetector. This model consists of a set of continuity equations for the density and energy together with constitutive relations for the particle and energy fluxes. These fluxes are expressed in terms of gradients of the entropic variables, through a diffusivity matrix related to the Boltzmann collision operators. In this formulation new Slothboom variables are defined instead of carrier concentrations. We discuss the finite difference discretization of the various differential subsystems, with special emphasis on their stability properties, and illustrate the performance of the proposed algorithms and models on the numerical simulation of devices in two spatial dimensions. A full implicit method is used to discretize the temporal derivatives. The carrier concentrations, carrier temperatures and electrostatic potential in each mesh points and each time steps are achieved. Finally the thermal diffusion, current density and the response of the MSM photodetector are calculated. The numerical results confirm with experimental results in a good manner. But high difference between the results with ignoring the thermal diffusion in room temperature, are not seen.

کلیدواژه ها:

electron transport ، energy transport ، semiconductor devices ، MSM Photodetector