CARRIER TRANSPORT AND I-V CHARACTERISTIC OF Au/Si SILICIDES USING OPEN PHOTOACOUSTIC CELL AND FOUR POINT-PROBE TECHNIQUES

Abstract

The carrier transport properties of Au/Si samples annealed at three temperatures (i.e., 100 °C, 363 °C and 800 °C) were investigated using the open photoacoustic cell (OPC) technique. A gold film of 45 nm was deposited on the silicon substrate and annealed in air environment. We observed that Au_8.1Si_1.9 silicide and Au₇Si(622) silicide were formed at both 363 °C and 800 °C annealing temperatures. Obviously the Au_8.1Si_1.9 silicide was observed in all Au/p-Si system. The result indicates that the recombination process increases with the formation of Au₇Si silicide. From the analysis of photoacoustic phase fitting and four point probe techniques, surface recombination velocity of gold silicide was found increase with the increasing annealing temperature. However, the band-to-band recombination lifetime decreased as annealing temperature increased. The I-V characteristic shows the Schottky curves for the annealing temperatures of 363 °C and 800 °C. This behavior is due to the formation of Au₇Si(622) silicide clusters.