Introduction to the Physics of Semiconductor Devices
- At temperatures lower or equal to room-temperature most of the free charge carriers
(electrons and holes) in semiconductors occupy states in the conduction band
minimum or valence band maximum, respectively.
- Idea: model the electron/hole dispersion relation by a parabola fitted to the
conduction band minimum / valence band maximum. Treat the free charge carriers
like free electrons with a modified mass.
- This mass is called the effective electron/hole mass meff.
- Please note that meff is often not isotropic!
Schematic illustration of the effective mass approximation.