Superlattice field effect transistor with monolayer confinement

摘要

A heterojunction field effect transistor (HFET) having a source, drain, and channel, wherein the channel is a top layer of a superlattice buffer, eliminating the need for a thick buffer layer. The superlattice buffer comprises alternating barrier and quantum well layers which are thin enough to provide wide separation in energy bands within the quantum wells. In a preferred embodiment the channel comprises a quantum well and one to five monolayers having a different bandgap than the channel region and serves to modify electron wave function and conduction band energy in the channel region. Preferably, a ten period AlAs/GaAs superlattice is formed underneath the channel.