range from about 300 u00b0 c to about 600 u00b0 c most preferrably process parameters are at a pressure in a range from about 100 atmospheres to about 700 atmospheres and a temperature range from about 400 u00b0 c to about 550 u00b0 c fig8 illustrates a two layer deposition in a second preferred alternative of the present invention the second preferred alternative has a step requiring high pressure low temperature trench channel or via filling this technique for substantially complete trench channel or via filling is accomplished by providing a semiconductor structure 310 having a recess 312 therein recess 312 which may be a trench channel or via has side walls and a bottom next a barrier layer 314 is deposited on the side walls and bottom of recess 312 over and upon barrier layer 314 a first metal alloy 316 is deposited upon barrier layer 314 first metal alloy 316 which has a first melting point with barrier layer 314 forms a device barrier layer metal composite 320 semiconductor structure 310 is then treated so that device barrier layer metal composite 320 forms a coherent composite a second metal alloy 318 is then deposited upon the coherent composite formed from device barrier layer.