Semiconductor Physics Terminology

These flashcards cover key terms and definitions related to semiconductor physics, focusing on conductivity, diffusion processes, and pn junction behaviors.

conductivity

A material parameter related to carrier drift; quantitatively, the ratio of drift current density to electric field.

diffusion

The process whereby particles flow from a region of high concentration to a region of low concentration.

diffusion coefficient

The parameter relating particle flux to the particle density gradient.

drift

The process whereby charged particles move while under the influence of an electric field.

Einstein relation

The relation between the mobility and the diffusion coefficient.

Hall voltage

The voltage induced across a semiconductor in a Hall effect measurement.

mobility

The parameter relating carrier drift velocity and electric field.

resistivity

The reciprocal of conductivity; a material parameter that is a measure of the resistance to current.

avalanche breakdown

The process whereby a large reverse-biased pn junction current is created due to the generation of electron–hole pairs.

carrier recombination

The process whereby an electron falls into an empty state in the valence band so that an electron-hole pair is annihilated.

excess carriers

The term describing both excess electrons and excess holes.

quasi-Fermi level

The quasi-Fermi level for electrons relates the nonequilibrium electron and hole concentrations to the intrinsic carrier concentration.

built-in potential barrier

The electrostatic potential difference between the p and n regions of a pn junction in thermal equilibrium.

depletion region

Another term for space charge region.

reverse bias

The condition in which a positive voltage is applied to the n region with respect to the p region of a pn junction.

varactor diode

A diode whose reactance can be varied in a controlled manner with bias voltage.

storage time

The time required for the excess minority carrier concentrations at the space charge edge to go from their steady-state values to zero.