Hot-wire chemical vapor deposition of silicon nanoparticles on fused silica

Silicon nanoparticles on fused silica have potential as recombination centers in infrared detectors due quantum confinement effects that result in a size dependent band gap. Growth on fused silica was realized by etching in HF, annealing under vacuum at 700-750 °C, and cooling to ambient temperature before ramping to the growth temperature of 600 °C. Silicon particles could not be grown in a thermal chemical vapor deposition (CVD) process with adequate size uniformity and density. Seeding fused silica with Si adatoms in a hot-wire chemical vapor deposition (HWCVD) process at a disilane pressure of 1.1 × 10^− 5 Pa followed by thermal CVD at a disilane pressure of 1.3 × 10^− 2 Pa, or direct HWCVD at a disilane pressure of 2.1 × 10^− 5 Pa led to acceptable size uniformity and density. Dangling bonds at the surface of the as-grown nanoparticle were passivated using atomic H formed by cracking H₂ over the HWCVD filament.