Characterizations of palladium silicides formed by rapid thermal annealing

High intensity quartz-halogen tungsten lamps with power densities of 10, 15, and 25 W/cm2 were used to form palladium silicide films. Metal films of 83–200 nm were evaporated on (100)-oriented single-crystal silicon and subsequently processed in vacuum for time intervals from 5 to 60 s. The electrical characteristics and the microstructure of the silicide films were studied by four-point probe, x-ray diffraction, Auger electron spectroscopy, scanning electron microscopy, and Rutherford backscattering spectroscopy. A nonuniform PdSi film with dendritelike surface topography is formed at 25 W/cm2. A somewhat discontinuous low resistance film of predominantly PdSi is formed at 15 W/cm2. The same power density, for contaminated samples, induces agglomeration upon processing. A uniform Pd2Si film with a resistivity of 27 μΩ cm is obtained at 10 W/cm2. Longer processing times result in nucleation and growth of PdSi from Pd2Si.