Nearly Perfect Polycrystalline, Large-Grained Silicon Arrays Formed at Low-Temperature Ambient by Local Pyrolysis

We report low-temperature ambient synthesis of high-quality, several micrometer thick polycrystalline silicon arrays on soda lime glass substrates by local pyrolysis, where SiH₄ gas is locally decomposed near and condensed on the resistively heated microheater arrays with an average growth rate of 50 nm/s. The silicon arrays had nearly perfect crystallinity and a minimum grain size larger than 0.2 μm, as determined by spatially resolved Raman spectroscopy and transmission electron microscopy. Boron-doped silicon arrays by the local pyrolysis was further fabricated to yield concentric p-i-n heterojunction arrays with rectifying current–voltage or photovoltaic characteristics.