The stoichiometry and hydrogen content of hot-wire (HW)-grown silicon nitride was examined as a function of SiH4/NH3 flow ratio. The effect of post-deposition hydrogenation treatment on overall film hydrogen content was determined. The hydrogen release properties in Si-rich and N-rich nitride layers were characterized by annealing treatments. Defect hydrogenation was studied using Fourier transform infrared spectroscopy on platinum-diffused silicon substrates. HW nitride layers were deposited onto diffused emitter String Ribbon silicon substrates, producing cells with comparable short circuit current density, open circuit voltage. fill-factor, and efficiency to those fabricated using plasma chemical vapor deposition nitride layers. (C) 2003 Elsevier Science B.V. All rights reserved.