Time-Resolved Reflectivity Measurement of The Pressure-Enhanced Crystallization Rate of Amorphous Si in a Diamond Anvil Cell

Abstract

The authors have measured the pressure dependence of the solid phase epitaxial growth (SPEG) rate of self-implanted Si (100) by using the in-situ time-resolved reflectivity technique in a high-temperature and high-pressure diamond anvil cell (DAC). With fluid argon as the pressure transmission medium, a clean and perfectly hydrostatic pressure environment is achieved around the sample. The external heating geometry employed in the DAC provides a uniform temperature across the sample. At temperatures in the range of 530-550 deg C and pressure up to 50 kbars (5 GPa), the growth rate is enhanced by up to a factor of ten over that at 1 atmosphere pressure. The results are characterized by a negative activation volume of approximately -3.0 cm/sup 3mole (-27% of the atomic volume). These preliminary results show a significantly weaker pressure dependence than does the previous work of Nygren et al. (1985), who found an activation volume of -8.7 cm/sup 3mole. The implications of these results for the nature of the defect responsible for thermal SPEG and irradiation enhanced SPEG is discussed.