modulation-doped field-effect transistor (MODFET)

A metal-semiconductor field-effect transistor in which a doped material forms a heterojunction with an undoped channel; the doped material supplies electrons to the undoped channel whose high electron mobility results in enhanced channel conductance.

NOTE 1 Typically an aluminum gallium arsenide layer is grown on an undoped gallium arsenide layer by an epitaxial growth technique.

NOTE 2 Other popularly used acronyms for this device are HEMT for high-electron-mobility transistor, SDHT for selectively doped heterostructure transistor, and TEGFET for two-dimensional electron-gas field-effect transistor.

References: 

JESD77-B, 2/00