Physical Vapor Transport (PVT)
Physical Vapor Transport (PVT) is a widely used method for the growth of compound semiconductor single crystals such as silicon carbide (SiC) or aluminum nitride (AlN). It is highly favored for its ability to produce high-purity and defect-free crystals. The development of PVT and its variations like the Lely method continue to be a significant area of research, with the goal of optimizing the growth conditions improving the properties of the resulting crystals.
The Process
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In the PVT process, polycrystalline source material (e.g. SiC or AlN powder) undergoes sublimation at a high temperature and low pressure. In a carrier gas (e.g. argon), the resulting vaporized source material species is transported to a cooler seed crystal, where they condense, contributing to crystal growth. Unlike Chemical Vapor Deposition (CVD), PVT does not involve a chemical reaction with the carrier gas. The quality and characteristics of the grown crystal are determined by a number of process parameters including source temperature, deposition temperature, partial pressure ratio, and residual gas pressure. |
Applications
Our PVT systems are essential for the high-volume production of high-quality SiC wafers. Their adaptability for R&D enhances innovation in semiconductor technology.