Investigation of self-aligned p++-GaAs/n-InGaP heterojunction field-effect transistors

p++-GaAs/n-InGaP heterojunction field-effect transistors (HJFETs) with a highly carbon-doped gate and a wide-gap channel were reported. A self-aligned T-shaped gate HJFET exhibits a gate of View the MathML source in length by depositing gate metal of View the MathML source. DC characteristics including a turn-on voltage of View the MathML source at View the MathML source, a gate-drain breakdown voltage up to View the MathML source, a drain-source breakdown voltage exceeding View the MathML source, a maximum available transconductance of View the MathML source and AC performances such as a unit-current gain frequency of View the MathML source, and a unit-power gain frequency of View the MathML source were obtained for a non-self-aligned HJFET. With a self-aligned processing structure, the transconductance and fmax were improved to View the MathML source and View the MathML source, respectively.