Gate capacitance-voltage characteristics of submicron-long-gate diamond field-effect transistors with hydrogen surface termination

Abstract

The radio-frequency characteristics of p -type diamond field-effect transistors with hydrogen surface termination were numerically analyzed using an equivalent-circuit model. From the gate-source capacitance (CGS) -voltage (VGS) results extracted from measured s parameters, the authors found a plateau in CGS within a certain VGS range. This means that a two-dimensional hole gas channel forms parallel to the surface and that the channel is separated by a thin energy-barrier layer with an infinite height from the gate metal. At a high negative VGS, as negative VGS is increased, CGS increases steeply. This results from holes penetrating the energy barrier. © 2007 American Institute of Physics.