Thermodynamic Aspects of the Growth of SiC Single Crystals using the CF‐PVT Process

Abstract

The main trends that govern the continuous-feed physical vapor transport (PVT), bulk-crystal-growth process is investigated experimentally, together with thermodynamic and computation fluid dynamics (CFD) calculations. Several chemical systems are considered. An analysis of the chemistry of every successive step (CVD, transfer, and PVT) is presented first. The effects of hydrogen and chlorine are then investigated. Then, the interaction between the different steps is discussed. The strong chemical interaction which exists between the CVD and the PVT zones is demonstrated to require the consideration of the whole process and not the two zones separately.

Synthesis of α-SiC from tetramethylsilane by chemical vapor deposition at high temperature

“…The application of TMS-based CVD has been expanded to the bulk growth of SiC single crystals using a continuous-feed physical vapor transport (CF-PVT) technique. 7,8) Since TMS is not a source of explosive or hazardous gases during the CVD process used to synthesize SiC, it is recognized as a reliable precursor for use in SiC synthesis. However, TMS contains 4 times more C than Si in its molecular composition, which makes it difficult to obtain the stoichiometric deposition of SiC through TMS-based CVD, especially at temperatures of over 1500 °C.…”

Bulk and epitaxial growth of silicon carbide

“…Toward better control of SiC growth, modeling and simulation of SiC sublimation growth have been extensively investigated [35][36][37][38]. Calculation of heat and mass transport during sublimation growth of SiC is standard technology.…”

Thermodynamic approach to the synthesis of silicon carbide using tetramethylsilane as the precursor at high temperature

“…Hence, TMS has been widely used as a precursor in the deposition of SiC films at relatively low temperatures, in which a SiC(b) phase is formed [7,8]. Moreover, TMS has been used to produce bulk SiC(b) single crystals by means of a continuous feed physical vapor transport (CF-PVT) technique, in which a solid SiC phase is dynamically generated from TMS in a CVD reactor and then sublimed in a PVT chamber [15,16]. However, a hexagonal polytype of SiC, SiC(a), is preferred to tetragonal polytypes of SiC, SiC(b), in commercialized applications including single crystalline substrates for LED/power electronic devices because it exhibits a high breakdown field and a high thermal conductivity.…”