Patent ID: 6787821
Filing Date: 2004-09-07
Classification: H01L

Abstract:
A compound semiconductor device comprising:a substrate formed of a first compound semiconductor; a buffer layer formed on the substrate; a graded channel layer formed on the buffer layer, said graded channel layer composed of a second compound semiconductor layer doped with an impurity, said second compound semiconductor layer selected from the group consisting of a InxGa1-xAs layer, a GaAs1-xSbx layer and a InxGa1-xSb layer (x: distribution), the distribution (x) being set to 0.8&lE;x<1, said distribution (x) has a peak in the inside of said graded channel layer in a thickness direction, thereby an energy band gap of the graded channel layer is made narrower in the inside than at both ends in the thickness direction; a barrier layer formed on the graded channel layer; a gate electrode formed on the barrier layer to come into Schottky-contact with the barrier layer; and a source electrode and a drain electrode formed on both sides of the gate electrode to flow a current into the graded channel layer via the barrier layer.