Hot wire radicals and reactions

Study on the role of filament temperature on growth of indium-catalyzed silicon nanowires by the hot-wire chemical vapor deposition technique

“…The increase in T f at ! 1500 C has the effect of exponentially increasing the decomposition probability of SiH 4 [18], and the impingement rate of the Si flux on the substrate [18,56]. As a result, the number of precursors reaching the NWs growth sites is also greater than before.…”

Film stoichiometry and gas dissociation kinetics in hot-wire chemical vapor deposition of a-SiGe:H

“…The relative constancy of α eff for germane implies that this molecule is less selective with regard to reactive sites, consistent with its lower thermodynamic stability and higher dissociation probability. However, secondary depletion reactions are expected to be important at our higher pressures [6] and we expect secondary depletion reactions to increase α eff with pressure. The observed constancy of α eff with pressure for germane is most likely due to the cancellation of site selectivity effects with increasing gas phase reactions and may actually imply some wire site selectivity for germane dissociation.…”

“…where α HW represents the dissociation probability for molecules incident on the filament itself, and N is the number of secondary gas phase depletion reactions per hot surface dissociation between the filament dissociation products and the feed gases that further deplete the feed gas (e.g. Si + SiH 4 ) [6]. In Figs.…”

Atomic hydrogen induced defect kinetics in amorphous silicon

“…The measurement took place under identical conditions in a separate experiment using GaAs ATR crystals mbar (prior to HW ignition). The filament was located 6.8 cm from the resonator surface which was heated to 120 °C, leading to a growth rate of ~ 2.5 nm/min under conditions where SiH3 is considered to be the dominant growth precursor [48][49][50]. Separate depositions studied using infrared spectroscopy reveal a dominant contribution of the lower stretching mode (LSM) and a 70% smaller contribution of the higher stretching mode (HSM) with a total hydrogen content of ~ 13 at%, pointing to a dominance of (di-)vacancies over nanosized voids in the material.…”