/ GaAs/AlGaAs selective etching method of heterojunction semiconductor device and method for manufacturing p-HEMT using the GaAs/AlGaAs selective etching method

摘要

The present invention, AlGaAs / a heterojunction semiconductor device comprising a heterojunction structure of GaAs relates to a GaAs / AlGaAs selective etching method, but using the wet etching method, the etching solution used is predetermined to a solution mixture of citric acid and potassium citrate there is characterized in that it uses a hydrogen peroxide solution are mixed at a weight ratio. The steps of how to use a GaAs / AlGaAs selective etching ragged such as high manufacturing the electron mobility transistors, formed in the GaAs buffer layer, InGaAs channel layer, AlGaAs spacer layer, and a GaAs cap layer on a GaAs substrate of semi-insulating sequentially with , GaAs cap comprising: layer forming a mask film pattern on, and etching the GaAs cap layer so that part of the surface exposure of the soaked the AlGaAs spacer layer to the exposure opening portion surface of the GaAs cap layer by a mask film pattern for etching solutions but, the etch solution comprises the step of using a hydrogen peroxide solution are mixed at a predetermined volume ratio to the solution of a mixture of citric acid and potassium citrate solution.