CVD in Weakly Rarefied Rotating Disk Flows

Abstract

CVD in a weakly rarefied rotating disk flow is numerically investigated using the SPIN code modified by including slip boundary conditions for velocity, concentration, and temperature, and thereby extending the capability of the code to describe weakly rarefied flows. A model reaction mechanism for silicon deposition, including the gas-phase decomposition of silane to silylene and the surface reactions of silane and silylene, is used in order to demonstrate rarefied gas effects. Results show that, by taking into account the temperature slip, the deposition rate decreases from its value based on the continuum model, mainly due to either the decrease of the concentration of silylene, which is the dominant deposition species at high temperatures, or the decrease of the sticking coefficient of silane, which is the dominant deposition species at low temperatures. Compared to that of the temperature slip, the influence on the deposition rate of the velocity and concentration slips is negligible.

An improved macroscale model for gas slip flow in porous media

“…The interest for studying slightly compressible gas slip-flow in channels of characteristic dimension comparable to the gas mean free path at the pressure and temperature under consideration is tremendous for many applications that encompass gas flow in microchannels and nanofluidic systems (Porodnov et al 1974;Harley et al 1995;Karniadakis et al 2005;Cai et al 2007), characterization of low permeable porous materials (Lasseux et al 2011;Profice et al 2012) involved in processes ranging from gas production (Darabi et al 2012), gas or nuclear waste storage, filtration and separation (Chmielewski & Goren 1972), composite manufacturing (Zhang et al 2009), among many others. Consequently, a great deal of interest may also be focused on the prediction and estimation of the coefficients governing the physics of gas transport at the macroscale.…”

Kinetic Modeling of Low Temperature Epitaxy Growth of SiGe Using Disilane and Digermane

“…The main contributing specie in this case is the SiH 2 radical which has a unity sticking coefficient on the dangling bonds according to the previous reports. 21 The growth rate for Si deposition can be calculated as follows:…”

Near Continuum Flows Over a Rotating Disk

“…They are not only limited to the one in the traditional continuum regime, which was already well studied. For example, they are related to material synthetisation [2] and other applications [3][4][5]. In processes such as chemical vapor deposition [2], a thin film can be synthesized with the use of a rotating disk reactor.…”

“…For example, they are related to material synthetisation [2] and other applications [3][4][5]. In processes such as chemical vapor deposition [2], a thin film can be synthesized with the use of a rotating disk reactor. The rotating disk contains the substrate that later will be impinged by a chemical mixing.…”