Patent ID: 6933543
Filing Date: 2005-08-23
Classification: H01L

Abstract:
1. A high frequency switch device comprising: an epitaxy substrate formed by sequentially stacking an AlGaAs/GaAs superlattic buffer layer, a first Si planar doping layer, an undoped first AlGaAs spacer, an undoped InGaAs layer, an undoped second AlGaAs spacer, a second Si planar doping layer having a doping density greater than that of the first Si planar doping layer, and an undoped GaAs/AlGaAs capping layer on a GaAs semi-insulated substrate; a source electrode and a drain electrode formed on the undoped GaAs/AlGaAs capping layer, thereby forming an ohmic contact with the undoped GaAs/AlGaAs capping layer; and a gate electrode formed between the source electrode and the drain electrode, thereby forming a Schottky contact with the undoped GaAs/AlGaAs capping layer.