SILICIDE OHMIC CONTACT TO GaAs
Original Publication Date: 1985-Feb-01
Included in the Prior Art Database: 2005-Feb-18
A codeposited layer of silicon and a metal that is reactive to Ga and a dopant of GaAs will serve as an improved ohmic contact to GaAs. An example is a coevaporated or cosputtered layer of Si and Pd. The layer is deposited on (100) or (110) oriented GaAs and is stable between 350ŒC and 500ŒC. The following advantages are involved: (a) Pd2Si and PdGa are the final phases formed at temperatures between 350 to 500ŒC. The contact structure is stable upon prolonged annealing. (b) Pd2Si and PdGa are good conductors. (c) The alloying reaction is uniform over the whole interfacial area. The contact is ideal for shallow junctions. (d) No second metal is needed to ensure the uniformity of the contact. The alloying reaction is, therefore, easier to control.