China single crystal sapphire wafer Manufacturers, Suppliers, Factory

In semiconductor fabrication, etching is one of the major steps, along with photolithography and thin-film deposition. It involves removing unwanted materials from the surface of a wafer using chemical or physical methods. This step is carried out after coating, photolithography, and developing. It is used to remove the exposed thin film material, leaving only the desired portion of the wafer, and then removing the excess photoresist. These steps are repeated numerous times to create complex integrated circuits.

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.

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 fabrication of semiconductor devices primarily encompasses four types of processes: (1) Photolithography (2) Doping Techniques (3) Film Deposition (4) Etching Techniques The specific techniques involved include photolithography, ion implantation, rapid thermal processing (RTP), plasma-enhanced chemical vapor deposition (PECVD), sputtering, and both dry and wet etching methods.

Both epitaxial and diffused wafers are essential materials in semiconductor manufacturing, but they differ significantly in their fabrication processes and target applications. This article delves into the key distinctions between these wafer types.

There are many types of gallium nitride (GaN), with silicon-based GaN being the most discussed. This technology involves growing GaN materials directly on a silicon substrate.