China Silicon-Based GaN Epitaxy Manufacturers, Suppliers, Factory

As a third-generation semiconductor material, Gallium Nitride is often compared with Silicon Carbide. Gallium Nitride still demonstrates its superiority with its large bandgap, high breakdown voltage, high thermal conductivity, high saturated electron drift velocity and strong radiation resistance. But it is undeniable that, like Silicon Carbide, Gallium Nitride also has various technical difficulties.

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.

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.

As a wide-bandgap (WBG) semiconductor material, SiC's wider energy difference gives it higher thermal and electronic properties compared to traditional Si. This feature enables power devices to operate at higher temperatures, frequencies and voltages.

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.

Crystal growth is the core link in the production of Silicon Carbide substrates, and the core equipment is the crystal growth furnace. Similar to traditional crystalline silicon-grade crystal growth furnaces, the furnace structure is not very complex and mainly consists of a furnace body, a heating system, a coil transmission mechanism, a vacuum acquisition and measurement system, a gas path system, a cooling system, a control system, etc., among which Thermal field and process conditions determine the quality, size, conductive properties and other key indicators of Silicon Carbide crystals.