Synthesis of large-grained poly-Ge templates by selective nucleation and solid phase epitaxy for GaAs solar cells on soda-lime glass

Abstract

Synthesis of large-grained (20–30 μm) polycrystalline Ge films on uncoated soda-lime glass substrates is demonstrated using selective nucleation and solid phase epitaxy. The Ge crystallization kinetics and film microstructure are very similar to those previously observed for Ge on thermally-oxidized Si substrates, implying that the selective nucleation and solid phase epitaxy process is unaffected by impurities in the glass or the microstructure of the Ge/glass interface. These large-grained Ge films on glass are being investigated as templates for heteroepitaxy of GaAs/glass low-cost thin film solar cells.