Introduction to Semiconductors
WHAT IS A SEMICONDUCTOR? Materials whose conductivity lies between those of conductors and insulators are called semiconductors. The most commonly used semiconductors are germanium(Ge) and silicon(Si). (google images) CONDUCTION OF SEMICONDUCTORS The conductivity and resistivity of materials depends mainly on the energy gap between conduction band and valence band. (google images) For conductors there is no electron gap and hence conduction band and valence band overlap each other. If large potential difference is applied across the valence band, then electrons jump into conduction band and hence conduct electrons. For silicon and germanium 1.1eV and 0.71eV needs to be applied for ele