Electroless Niekel-Tungsten-Phosphorus Plating on the Surface of Gallium Arsenide Single Crystals

摘要

The results of this investigation of Ni-W-P alloy electroless plating from a nickel-hypophosphite bath on GaAs single crystal surface are considered. It has been found that in order to obtain high adhesion strength at the semiconductor-metal interface, it is expedient to etch the GaAs surface for 2 min at room temperature in one of two solutions (volume ratios): H_2SO_4:H_2O_2:H_2O = 18.1:1 or NH_4OH:H_2O_2:H_2O = 2:8:3 and to deposit the alloy at 80-90℃ at a pH of 7-9 from a solution of the following formulation: 0.03M NiSO_4 0.07M Na_2WO_4 0.10M Na_3C_6H_7O_8 0.10M NaH_2PO_2 The alloy films, 1-μm thick, produced under these conditions, contain 6.9, 9.3, and 83.8 atomic % of tung-sten, phosphorus, and nickel, respectively.