High-Throughput Thermodynamic Analysis of TaC Coatings by Chemical Vapor Deposition

Abstract

For guiding the growth regulation of high-purity TaC coatings for semiconductor high-temperature furnace components, the high-throughput thermodynamic simulation calculation of TaC coating growth process was carried out by Thermo-calc software, and the effects of deposition temperature, pressure and precursor component ratio on raw material utilization efficiency and TaC coating purity were investigated. Simulation results demonstrated that X(Ta)∶X(C)(Mole fraction ratio) determined the phase composition of the products, while X(H)∶X(C) defined the formation window of the high-purity TaC coating in the “TaCl5+C3H6+H2” system. When X(Ta)∶X(C)<1, high-quality TaC coatings could be obtained, and the free carbon was the primary impurity in the coating, which could be eliminated by elevating hydrogen concentration in the atmosphere. According to the simulation analysis results, the recommended reaction window was X(Ta)∶X(C) of 0.8～1.0 and X(H)∶X(C)≥400, the deposition temperature of 1 800～2 100 K and deposition pressure of 5 000～10 000 Pa. Under the above conditions, the high purity(>99%) and high material utilization(>99%) TaC coatings could be obtained.

Keywords

• thermodynamics; chemical process;tac; deposition; coatings