* Corresponding author. E-mail address: palpuim@fisica.uminho.pt (P. Alpuim) 1 Deposition of Silicon Nitride Thin Films by Hot-Wire CVD at 100ºC and 250ºC P. Alpuim 1 * , L.M. Gonçalves 2 , E.S. Marins 1 , T.M.R. Viseu 3 , S. Ferdov 1 , J.E. Bourée 4 1 Departamento de Física, Universidade do Minho, 4800-058 Guimarães, Portugal 2 Departamento de Electrónica Industrial, Universidade do Minho, 4800-058 Guimarães, Portugal 3 Departamento de Física, Universidade do Minho, 4710-057 Braga, Portugal 4 Laboratoire de Physique des Interfaces et des Couches Minces, CNRS UMR 7647, Ecole Polytechnique, 91128 Palaiseau, France Abstract Silicon nitride thin films for use as passivation layers in solar cells and organic electronics or as gate dielectrics in thin-film transistors were deposited by the Hot-wire chemical vapor deposition technique at a high deposition rate (1-3 Ǻ/s) and at low substrate temperature. Films were deposited using NH 3 /SiH 4 flow rate ratios between 1 and 70 and substrate temperatures of 100º C and 250ºC. For NH 3 /SiH 4 ratios between 40 and 70, highly transparent (T ~ 90%), dense films (2.56 - 2.74 g/cm 3 ) with good dielectric properties and refractive index between 1.93 and 2.08 were deposited on glass substrates. Etch rates in BHF of 2.7 Ǻ/s and <0.5 Ǻ/s were obtained for films deposited at 100ºC and 250ºC, respectively. Films deposited at both substrate temperatures showed electrical conductivity ~ 10 -14 Ω -1 cm -1 and breakdown fields >10 MV cm −1 . Keywords Hot-wire CVD, silicon nitride, dielectric, low-temperature deposition, electronic transport