The variety of catalysts based on macroporous supported ionic liquid-like phases using chloromethyl styrene cross-linked with divinylbenzene (CMS/DVB) and different NR3 cations was investigated for disproportionation of trichlorosilane in a continuous-flow reactor. To determine the optimal conditions for conducting a complex catalytic process, the primary task is to determine the thermodynamical equilibrium state of the reaction system. Increase in the concentration of DCS in the system occurs from 5 to 10%, which in turn is promising in terms of considering DCS as the main precursor for the processes of epitaxial silicon growth. In addition, the maximum attainable temperature is thermodynamically optimal for the process. In the first stage, the thermal stability of the catalyst supports was determined using evolved gas analysis and all samples have a similar thermal stability 475 К. All samples have been carefully studied by SEM, AFM, EGA and nitrogen physisorption. To compare the catalytic activity of different catalytic systems on the basis of macroporous supports modified by different tritic ammonium functional groups with the subsequent activation, the kinetics of the TCS disproportionation on the catalyst sample having the highest catalytic activity was studied. The results obtained indicate that the introduction of acceptor substituents increases catalytic activity in the disproportionation of TCS. To assess the feasibility of using dichlorosilane (DCS) as a raw material for the creation of semiconductor structures, the kinetics of thermal decomposition of DCS in a mixture with hydrogen was studied at a temperature of 1200–1500 K. According to the obtained kinetic results, the activation energy of the process is determined, which is in the temperature range of 1220–1320 K and the concentration of DCS in hydrogen 9–28.6 mol.%, is 112.9 kJ/mol. Activation energy value indicates the kinetical mode of the thermal decomposition.

Supported ionic liquid-like phases based on CMS/DVB with different NR3 cations as catalysts for the chlorosilanes disproportionation

Film thickness uniformity is an important index to measure the quality of a deposited layer in selective epitaxial growth (SEG) of silicon using the chemical vapor deposition (CVD) process. The uniformity of a thin film is related to many parameters, such as rotation speed of a wafer, total flow rate, species concentration, susceptor temperature, and operating pressure. Therefore, it is very important to address the problem of coupling multiple parameters and solve the optimization in a computationally efficient manner. In this work, response surface methodology (RSM) is used to analyze the complex coupling effects of different operating parameters on silicon deposition uniformity. Based on the computational fluid dynamics (CFD) model, an accurate RSM model is obtained to predict non-uniformity with different parameters, including temperature, pressure, rotation speed of a wafer, and mole fraction of dichlorosilane (DCS). Analysis of variance (ANOVA) is conducted to determine the statistical significance of each factor in an empirical equation for the expected response. The results of ANOVA analysis indicate the goodness of fit of the regression model. The optimum combination of operating parameters of the problem considered in this study is a susceptor temperature of 1122.2 K, wafer rotation speed of 23.72 rpm, operating pressure of 112 Torr, and DCS mole fraction of 0.01186. The validation tests and optimum solution show that the results are in good agreement with those from the CFD model, and the maximum deviation between the computational solution and predicted values is 2.93%.

Optimization of Operating Parameters in a Planetary CVD Reactor Using Response Surface Methodology

Silicon chemical vapor deposition via silane is determined with classical thermodynamics. Drastic assumptions are used, such as the hydrogen carrier gas does not interact with the silicon thin film...

Thermodynamic Theory of Silicon Chemical Vapor Deposition

Multi-wafer planetary type chemical vapor deposition (CVD) reactors are widely used in thin film growth and suitable for large scale production. In this paper, numerical modeling has been carried out to simulate transport phenomena and epitaxial silicon growth in a planetary CVD reactor for the SiH2Cl2–H2–HCl system. A chemical reaction model using temperature dependent reaction rate is proposed and validated using experimental data. Based on the model, the effect of various operation conditions such as satellite rotational speed, species concentration, operating temperature and pressure is considered to determine the key factor influencing the growth rate and uniformity. The results reveal that the growth rate and uniformity are strongly related to total flow rate, species concentration and operating pressure, but are not affected by rotational speed of the satellite in case of high flow rates. Growth rates are found to be increased from 0.02 $\mu \text{m}$ /min at operating pressure of 10 torr to approximately 0.16 $\mu \text{m}$ /min at 150 torr. Growth deposition non-uniformity decreases from 80% for total flow rate of 460 slm to 13% for total flow rate of 46 slm.

Modeling of Epitaxial Silicon Growth From the DCS-H 2 -HCl System in a Large Scale CVD Reactor

Pressure dependence of rate coefficients of unimolecular and chemical activation reactions connected to the potential energy wells of chlorinated monosilanes by RRKM calculations

Yeon-Ho Jang

Papers

Numerical modeling study on the epitaxial growth of silicon from dichlorosilane