The kinetics of dopant-enhanced solid phase epitaxy in H-free amorphous silicon layers

Abstract

The kinetics of intrinsic and dopant-enhanced solid phase epitaxy (SPE) have been measured in the H-free environment provided by buried amorphous Si layers formed by MeV ion implantation. The dopant-enhanced SPE kinetics were studied in buried a-Si layers containing uniform As concentration profiles produced by multiple energy ion implantation to doses spanning the concentration range 1–28×10 19 As/cm 3 and the crystallisation rates were measured over the temperature range 460–660°C using time-resolved reflectivity. The dopant-enhanced SPE data can be modelled by an extension of the Generalised Fermi Level Shifting model (GFLS) to take into account the degenerate semiconductor statistics on the crystalline Si side of the interface and by estimating the effect of band bending at the amorphous/crystalline (a/c) interface.