Undoped and arsenic-doped low temperature (similar to 165 degrees C) microcrystalline silicon for electronic devices process

摘要

Microcrystalline silicon films are deposited at 165 degrees C by plasma enhanced chemical vapor deposition (PECVD) from silane, highly diluted in hydrogen-argon mixtures. Ar addition during the deposition allows to increase the crystallinity from 24% to 58% for 20 nm thick films. The final crystallinity for 350 nm thick films reaches 72% with an increase in the grain size. A further increase, still 80%, is provided by substrate pre-treatment using hydrogen plasma before the deposition process. Arsenic doped mu c-Si films, deposited on previous optimized (5 W power and 1.33 mbar pressure) undoped films without stopping the plasma between the deposition of both layers, show high electrical conductivity up to 20 S cm(-1). (c) 2006 Elsevier B.V. All rights reserved.