Carrier concentration and transport

Abstract

The semiconductor devices operate based upon the charge control, and two factors are involved in the control, namely the concentration and transport of charge carriers. This chapter is addressed to these two basic quantities. The concentration depends upon the doping level, temperature, and other electronic properties of the semiconductor and will be discussed, starting from the Fermi and Boltzmann distribution functions. The carrier transport in semiconductor devices has been attributed primarily to the drift and diffusion. With the downsizing of the semiconductor devices, however, the ballistic transport becomes important as well as tunneling. The transport processes are compactly discussed.