China SiN film Manufacturers, Suppliers, Factory

In the semiconductor industry, epitaxial layers play a crucial role by forming specific single-crystal thin films atop a wafer substrate, collectively known as epitaxial wafers. Particularly, silicon carbide (SiC) epitaxial layers grown on conductive SiC substrates produce homogenous SiC epitaxial wafers, which are instrumental in the fabrication of power devices such as Schottky diodes, MOSFETs, and IGBTs, with 4H-SiC substrates being the most widely utilized.

Currently, many semiconductor devices employ mesa device structures, which are predominantly created through two types of etching: wet etching and dry etching. While the simple and rapid wet etching plays a significant role in semiconductor device fabrication, it has inherent drawbacks such as isotropic etching and poor uniformity, which result in limited control when transferring small-sized patterns. Dry etching, however, with its high anisotropy, good uniformity, and repeatability, has become prominent in semiconductor device fabrication processes. The term “dry etching” broadly refers to any non-wet etching technology used for removing surface materials and transferring micro and nano patterns, including laser etching, plasma etching, and chemical vapor etching. The dry etching discussed in this text specifically pertains to the narrow application of processes using plasma discharge—either physical or chemical—to modify material surfaces.

Etching is an essential process in semiconductor manufacturing. This process can be categorized into two types: dry etching and wet etching. Each technique has its own advantages and limitations, making it crucial to understand the differences between them. So, how do you choose the best etching method? What are the pros and cons of dry etching and wet etching?

In the process of wafer preparation, there are two core links: one is the preparation of the substrate, and the other is the implementation of the epitaxial process. The substrate, a wafer carefully made of semiconductor single crystal material, can be directly put into the wafer manufacturing process as a basis to produce semiconductor devices, or further enhance the performance through the epitaxial process.

Single crystal silicon and polycrystalline silicon each have their own unique advantages and applicable scenarios. Single crystal silicon is suitable for high-performance electronic products and microelectronics due to its excellent electrical and mechanical properties. Polycrystalline silicon, on the other hand, dominates the field of solar cells due to its low cost and good photoelectric conversion efficiency.

Silicon carbide (SiC), as an important high-end ceramic material, has excellent properties such as high-temperature resistance, corrosion resistance, wear resistance, high-temperature mechanical strength, and oxidation resistance. These properties make it highly promising for applications in high-tech fields such as semiconductors, nuclear energy, defense, and space technology.