Liquid-Phase Epitaxy

Abstract

The long history of liquid-phase epitaxy (LPE) is surveyed starting at its origins around 1960 up to recent applications for making narrow- and wide-bandgap semiconductor surrogate substrates. Various modes of LPE are described, including transient cooling, and growth induced and sustained by temperature gradients, electric currents and magnetic fields, chemical reactions and potential gradients using metastable sources, solvent evaporation, forced flow, surface and capillary effects, and centrifugal forces. This chapter also covers special or unique features of LPE that can serve niche applications based on high growth rates, lower temperatures, wide choice of dopants including rare earths for gettering, high material quality, and adaptations of LPE for selective epitaxy, epitaxial lateral overgrowth, and bulk crystal growth. Work assessing the feasibility of LPE-like processes for low-cost silicon solar cell production, both for purification and high-throughput deposition, is also reviewed.