Fabrication of submicron etch resistant metal / semiconductor structures using resistless electron beam lithography

摘要

A method for fabricating a sub-micron structure of etch-resistant metal/semiconductor compound on a substrate of semiconductor material comprises the step of depositing onto the substrate a layer of metal capable of reacting with the semiconductor material to form etch-resistant metal/semiconductor compound, and the step of producing a focused electron beam. The focused electron beam is applied to the layer of metal to locally heat the metal and semiconductor material and cause diffusion of the metal and semiconductor material in each other to form etch-resistant metal/semiconductor compound. The focused electron beam is displaced onto the layer of metal to form the structure of etch-resistant metal/semiconductor compound. Finally, the layer of metal is wet etched to leave on the substrate only the structure of metal/semiconductor compound. Following wet etching of the layer of metal, an oxygen plasma etch can be conducted to remove a carbon deposit formed at the surface of the structure of etch-resistant metal/semiconductor compound. Also, the substrate may be subsequently etched to remove a thin layer of metal rich semiconductor material formed at the surface of the substrate by reaction, at room temperature, of the metal and semiconductor material with each other.