Electrically Transparent Etch-Stop Layer
Original Publication Date: 1988-Jan-01
Included in the Prior Art Database: 2005-Feb-14
Proposed is an extremely thin etch-stop layer that allows accurate process control in the fabrication of semiconductor devices without affecting the electrical characteristics of the completed devices. It is demonstrated, how such etch-stop layers, consisting of AlAs, may be used in the fabrication of enhancement (E)- and depletion (D)-type GaAs MESFETs. The proposed etch-stop layer, having an etch-rate different from that of adjacent layers, has the sole function of defining vertical dimensions of the final device structure. In order not to affect the device characteristics, the layer is to be electrically "transparent" so it does not need to be removed or changed in any way to obtain a fully functional device.