Method of fabricating self-aligned FET structure having a high temperature stable T-shaped Schottky gate contact

A method of fabricating a self-aligned FET comprising the steps of:

• providing a substrate having a surface:
• forming a conductive channel in the substrate adjacent the surface;
• depositing a layer of TiWN refractory gate metal on the surface of the substrate to form a Schottky gate contact on the substrate;
• selectively depositing a layer of LaB.sub.6 on the layer of TiWN by electron beam deposition and photolithography;
• selectively dry etching the layer of TiWN, using the layer of LaB.sub.6 as a mask, to form a high temperature stable "T-shaped" Schottky gate contact on the surface of the substrate in overlying relationship to the conductive channel;
• implanting a dopant into the substrate to form source and drain regions in overlying relationship to the conductive channel adjacent to the surface in spaced relationship to the "T-shaped" gate and in spaced apart relationship using the "T-shaped" Schottky gate contact as a mask;
• annealing the implanted source and drain regions;
• and
• selectively depositing metal to form source and drain ohmic contacts on the surface of the substrate in overlying relationship to the source and drain ohmic regions using the "T-shaped" Schottky gate contact as a mask.