The Effect of Potassium on the Rate of Solid Phase Epitaxy in Silicon

Abstract

Rutherford backscattering spectroscopy and ion channeling and secondary ion mass spectroscopy have been used to study the evolution of a potassium profile in amorphous silicon during solid phase epitaxial crystallisation. The potassium profile exhibits some propensity for refinement in front of the crystallising interface for the concentrations used in this experiment. Also, the potassium is partially substitutional in the crystallised layer. Preliminary studies on the influence of potassium on the rate of solid phase epitaxy (SPE) in silicon are presented. Surface amorphous films doped with potassium were crystallised and the rate of epitaxy was monitored using time resolved reflectivity. The inclusion of potassium was found to retard the rate of SPE. These results indicate that potassium doped amorphous films may be helpful in efforts to further refine present models of SPE in silicon.