Si_1-x-yGe_xC_y Growth and Properties of the Ternary System

Abstract

Molecular Beam Epitaxy has been used to grow Si_1-yC_y and Si_l-x-yC_yGe_x alloys. This allows some degree of independence between strain and bandgap in Si based semiconductors. Unlike the Si-Ge system the Si-C system has a high misfit (52%) and low solubility (> 10^-6), with a propensity to compound formation, therefore, the structures are kinetically stabilized by low temperature growth. In this work, we first describe bandgap engineering applied to this system. We then consider the growth methodology and critical thickness. Strain compensation and strain engineering using the ternary system is then described. Finally we show that thermal degradation of these films does not occur till < 800°C first by interdiffusion and subsequently at higher temperatures by silicon carbide precipitation