Modeling of Hydrogen Diffusion And Segregation in Amorphous Silicon During Solid Phase Epitaxy

The diffusion and segregation of hydrogen in surface amorphous silicon layers during solid phase epitaxy (SPE) is modeled. The SPE and H concentration profiles from J. Roth et al., Mat. Res. Soc. Symp. Proc. 205, 45 (1992) are used to test H segregation and diffusion models. Excellent agreement is obtained with a trap limited diffusion model. This model has previously been found to describe the diffusion of fluorine well. The H segregation coefficient at the crystalline-amorphous interface is determined at a temperature of 606oC to be 0.064. The possible temperature dependence of the segregation coefficient and its effect on SPE are also discussed.