China Semiconductor Epitaxy Manufacturers, Suppliers, Factory

SiC's own characteristics determine its single crystal growth is more difficult. Due to the absence of Si:C=1:1 liquid phase at atmospheric pressure, the more mature growth process adopted by the mainstream of the semiconductor industry can not be used to grow the more mature growth method-straight pulling method, the descending crucible method and other methods for growth. After theoretical calculations, only when the pressure is greater than 105 atm and the temperature is higher than 3200 ℃, can we get the stoichiometric ratio of Si:C = 1:1 solution. pvt method is currently one of the more mainstream methods.

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 growth of GaN epitaxy on GaN substrate presents a unique challenge, despite the material’s superior properties when compared to silicon. GaN epitaxy offers significant advantages in terms of band gap width, thermal conductivity, and breakdown electric field over silicon-based materials. This makes the adoption of GaN as the backbone for the third generation of semiconductors, which provide enhanced cooling, lower conduction loss, and improved performance under high temperatures and frequencies, a promising and crucial advancement for the photonic and micro-electronic industries.

The first generation of semiconductor materials is mainly represented by silicon (Si) and germanium (Ge), which began to rise in the 1950s. Germanium was dominant in the early days and was mainly used in low-voltage, low-frequency, medium-power transistors and photodetectors, but due to its poor high temperature resistance and radiation resistance, it was gradually replaced by silicon devices in the late 1960s. Silicon is still the main semiconductor material in the field of microelectronics due to its high technological maturity and cost advantages.

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.

Silicon nitride (Si3N4) is a key material in the development of advanced high-temperature structural ceramics.