Print Email Facebook Twitter Hydrogenated amorphous silicon deposited under accurately controlled ion bombardment using pulse-shaped substrate biasing Title Hydrogenated amorphous silicon deposited under accurately controlled ion bombardment using pulse-shaped substrate biasing Author Wank, M.A. Van Swaaij, R.A.C.M.M. Kudlacek, P. Van de Sanden, M.C.M. Zeman, M. Faculty Electrical Engineering, Mathematics and Computer Science Department Electrical Sustainable Energy Date 2010-11-18 Abstract We have applied pulse-shaped biasing to the expanding thermal plasma deposition of hydrogenated amorphous silicon at substrate temperatures ? 200?°C and growth rates around 1 nm/s. Substrate voltage measurements and measurements with a retarding field energy analyzer demonstrate the achieved control over the ion energy distribution for deposition on conductive substrates and for deposition of conductive materials on nonconductive substrates. Presence of negative ions/particles in the Ar–H2–SiH4 plasma is deduced from a voltage offset during biasing. Densification of the material at low Urbach energies is observed at a deposited energy <4.8?eV/Si atom and attributed to an increase in surface mobility of mobile species as well as well as surface atom displacement. The subsequent increase in Urbach energy >4.8?eV/Si atom is attributed to bulk atom displacement in subsurface layers. We make the unique experimental abservation of a decreasing Tauc band gap at increasing total hydrogen concentration—this allows to directly relate the band gap of amorphous silicon to the presence of nanovoids in the material. Subject amorphous semiconductorscarrier mobilitydensificationelemental semiconductorsenergy gaphydrogenplasma depositionsemiconductor growthsemiconductor thin filmssilicon, voids (solid) To reference this document use: http://resolver.tudelft.nl/uuid:cf0627a5-f66b-4588-b90e-4a8b089ca635 DOI https://doi.org/10.1063/1.3505794 Publisher American Institute of Physics ISSN 0021-8979 Source http://jap.aip.org/resource/1/japiau/v108/i10/p103304_s1 Source Journal of Applied Physics, 108 (10), 2010 Part of collection Institutional Repository Document type journal article Rights (c) 2010 The Author(s)American Institute of Physics Files PDF Wank_2010.pdf 295.05 KB Close viewer /islandora/object/uuid:cf0627a5-f66b-4588-b90e-4a8b089ca635/datastream/OBJ/view