Semiconductors: Basic Properties

This lecture covers the basic properties of semiconductors, including the increase in conductivity with temperature, the influence of impurities on properties, and the role of holes in conductivity. It also discusses the temperature dependence of semiconductors and metals, intrinsic behavior at high temperatures, band gap measurements through optical absorption, and direct vs. indirect band gaps. The lecture concludes with a focus on crystal structures of Si, Ge, and GaAs, as well as real band structures using Ge as an example.