China Carbon Fiber Reinforced Sic Boats Manufacturers, Suppliers, Factory

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 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.

The four main molding methods for graphite molding are: extrusion molding, molding, vibratory molding and isostatic molding. Most of the common carbon/graphite materials on the market are molded by hot extrusion and molding (cold or hot), and isostatic molding is a method with leading molding performance. Vibration molding is generally used to manufacture medium and coarse structural graphite, particle size between 0.5-2mm particle size, generally dominated by di-roasted graphitized products, density between 1.55-1.75kg/m³, coarser particles, rougher surface, can not be used for precision machining. It is mainly used in chemical industry and metal smelting.

According to reports from German media, U.S. chip manufacturer Wolfspeed is pausing its plans to build a semiconductor plant in Germany.

One of the unique properties of semiconductor materials is that their conductivity, as well as their conductivity type (N-type or P-type), can be created and controlled through a process called doping. This involves introducing specialized impurities, known as dopants, into the material to form junctions on the surface of the wafer. The industry employs two main doping techniques: thermal diffusion and ion implantation.