China bell vacuum chamber Manufacturers, Suppliers, Factory

Gallium Nitride (GaN) epitaxial wafer growth is a complex process, often utilizing a two-step method. This method involves several critical stages, including high-temperature baking, buffer layer growth, recrystallization, and annealing. By meticulously controlling the temperature throughout these stages, the two-step growth method effectively prevents wafer warping caused by lattice mismatch or stress, making it the predominant fabrication method for GaN epitaxial wafers globally.

In the process of growing SiC and AlN single crystals by the physical vapor transport method (PVT), components such as the crucible, seed crystal holder and guide ring play a vital role. During the preparation process of SiC, the seed crystal is located in a relatively low temperature region, while the raw material is in a high temperature region exceeding 2400°C. The raw materials decompose at high temperatures to form SiXCy (including Si, SiC₂, Si₂C and other components).

​In the realms of semiconductor technology and microelectronics, the concepts of substrates and epitaxy hold significant importance. They play critical roles in the manufacturing process of semiconductor devices. This article will delve into the differences between semiconductor substrates and epitaxy, covering their definitions, functions, material structures, and application areas.

The degree of graphitization is an essential measure used to assess how close carbon atoms are to forming a tightly-packed hexagonal graphite crystal structure.

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.

The development of 3C-SiC, a significant polytype of silicon carbide, reflects the continuous advancement of semiconductor material science. In the 1980s, Nishino et al. first achieved a 4 μm thick 3C-SiC film on a silicon substrate using chemical vapor deposition (CVD)[1], laying the foundation for 3C-SiC thin-film technology.