Explanation of the limiting thickness observed in low-temperature silicon epitaxy

Abstract

Solution of the partial differential equation for diffusion of mobile atoms during solid film growth demonstrates that the observed phase transition in low-temperature silicon epitaxy is triggered by supersaturation of the growing layer with hydrogen. The limiting thickness of the epitaxial layer, hepi, is completely determined by measurable quantities: the flux of hydrogen, the hydrogen diffusion coefficient, and the layer growth rate. Our model accounts for the observed Arrhenius and growth rate dependence of hepi.