Patent ID: 6929987

Claim:
A method of forming independent metallic contacts to each channel in a semiconductor device having at least a first channel layer formed over a portion of a second channel layer, the method comprising: applying a photoresist layer over the at least one first channel layer; exposing the device to a preselected etching solution to remove a predetermined portion of the second channel layer underlying the at least one first channel layer such that a portion of the at least one first channel layer overhangs the second channel layer, the etching solution selected to have no substantial effect on the photoresist layer; removing the photoresist layer; applying a first metallic contact to the portion of the at least one first channel layer overhanging the second channel layer; applying a second metallic contact to the second channel layer; and exposing the device to an ohmic alloying process to diffuse the metallic contacts into the first and second channel layers, respectively.