Deposition of amorphous silicon using a tubular reactor with concentric-electrode confinement

Abstract

High-quality, hydrogenated amorphous silicon (a-Si:H) is deposited at room temperature by rf glow discharge at a high deposition rate using a tubular reactor with cylindrical symmetry (concentric-electrode plasma-enhanced chemical vapor deposition, CE-PECVD). Using the novel CE-PECVD design, room-temperature deposition of a-Si:H with growth rates up to 14 Å s−1, low hydrogen concentration (≲10%), and the bonded hydrogen in the Si-H monohydride configuration, is achieved for the first time using an rf glow-discharge technique. The influence of the deposition parameters (silane flow rate, pressure, and power density) on the growth rate, optical band gap, and silicon-hydrogen bonding configuration, is quantitatively predicted using a deposition mechanism based on the additive contribution of three growth precursors, SiH2, SiH3, and Si2H6, with decreasing sticking coefficients of 0.7, 0.1, and 0.001, respectively. The low hydrogen concentration is due to the enhanced ion bombardment resulting from the concentric electrode design.

Properties of SiGe Films Fabricated by Reactive Thermal Chemical Vapor Deposition Using Lamp Heating

“…As the sticking coefficient of SiH 2 is a relatively high value of 0.7, 20,21) the surface diffusion of this species should be small so that the selective growth at the crystal formation site is suppressed. Therefore, the amorphous network is likely to be formed with this species of SiH 2 .…”

A control oriented modeling methodology for plasma enhanced chemical vapor deposition processes

“…Let H and 4 be functions that satisfy the following differential inequalities: (15) -gcos(@)+Fsin(@) dx …”