China MOCVD Epitaxy Manufacturers, Suppliers, Factory

The CVD process for SiC wafer epitaxy involves the deposition of SiC films onto a SiC substrate using a gas-phase reaction. The SiC precursor gases, typically methyltrichlorosilane (MTS) and ethylene (C2H4), are introduced into a reaction chamber where the SiC substrate is heated to a high temperature (usually between 1400 and 1600 degrees Celsius) under a controlled atmosphere of hydrogen (H2).

Heat treatment is one of the essential and important processes in the semiconductor process. Thermal process is the process of applying thermal energy to a wafer by placing it in an environment filled with a specific gas, including oxidation/diffusion/annealing, etc.

Quartz (SiO₂) material is very similar to glass at first glance, but the special thing is that the general glass is made up of many components (such as quartz sand, borax, boric acid, barite, barium carbonate, limestone, feldspar, soda ash, etc.), while the quartz contains only SiO₂ components, and the microstructure of its silicon dioxide tetrahedral structural units composed of a simple network.

The Silicon Carbide (SiC) production process encompasses the preparation of substrate and epitaxy from the materials side, followed by chip design and manufacturing, device packaging, and finally, distribution to downstream application markets. Among these stages, substrate material processing is the most challenging aspect of the SiC industry. SiC substrates are both hard and brittle, making cutting, grinding, and polishing extremely difficult. This increases the likelihood of defects during processing and reduces the yield rate. Currently, major international SiC manufacturers are planning to transition from 6-inch to 8-inch SiC wafers. Overcoming the challenges associated with 8-inch substrates has become a critical benchmark for the SiC industry. This article will introduce the key parameters of SiC substrates.

Within the silicon carbide (SiC) industry chain, substrate suppliers hold significant leverage, primarily due to value distribution. SiC substrates account for 47% of the total value, followed by epitaxial layers at 23%, while device design and manufacturing constitute the remaining 30%. This inverted value chain stems from the high technological barriers inherent to substrate and epitaxial layer production. Three major challenges plague SiC substrate growth: stringent growth conditions, slow growth rates, and demanding crystallographic requirements. These complexities contribute to increased processing difficulty, ultimately resulting in low product yields and high costs. Furthermore, the epitaxial layer’s thickness and doping concentration are critical parameters directly impacting the final device performance.

Plasma Enhanced Chemical Vapor Deposition (PECVD) is a widely used technology in chip manufacturing. It utilizes the kinetic energy of electrons within plasma to activate chemical reactions in the gas phase, thereby achieving thin-film deposition.