Experimental Study of Equilibrium Conditions in the Si‐H‐Cl System

Abstract

Thermodynamic studies of the Si‐H‐Cl system are widely available. The results of these studies vary due to differences in the number of gas‐phase components used and differences in the basic thermodynamic data employed. This work describes the first experimental study to determine the equilibrium Si/Cl ratio as a function of Cl/H and temperature. The experimental results fall near those which are calculated, though they do not uniquely support any one of the theoretical studies. Computational studies make the assumption that the Cl/H ratio is constant for the silicon CVD reaction. It is shown in this study that this is not always the case, particularly when there is substantial condensation of polychlorosilanes.

Thermodynamic Equilibria in the Si‐H‐Cl and Si‐H‐Br Systems

“…Woodruff and Sanchez-Martinez ( 23) have compared experimentally measured equilibrium data to calculated values by Hunt and Sirtl (3) and by themselves. The Si/ C1-C1/H data in this paper closely agree with that reported by Woodruff and Sanchez-Martinez (23). In general, experimental Si/C1 values are slightly lower than calculated values for temperatures from 1250 to 1450 K and at 1 bar total pressure.…”

Thermodynamic analysis of manufacturing polysilicon from SiHCl3, SiCl4 and H2

“…The calculated equilibrium composition is also consistent with the experimental results of Woodruff and Sanchez-Martinez [26], as shown in Fig. 3(c).…”

Thermodynamics of the Silicon‐Chlorine‐Hydrogen System: Chemical Potential for Homogeneous Nucleation

“…Previous workers primarily concerned with equilibrium species distributions have performed calculations for the gas-solid Si-C1-H system (7,8). The results of such calculations are in satisfactory agreement with experiment (9).…”

“…The degradation behavior of fl-and ~'-alumina electrolytes in Na]S cells has been studied by several investigators, and various mechanisms have been proposed. Notable among these mechanisms are impurity diffusion (1-4), dendritic penetration of metallic sodium during charge (5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15), and electron injection (16). However, little attention has been paid to the thermodynamic stability of these electrolytes in Na/S cells.…”