China alumina semiconductor Manufacturers, Suppliers, Factory

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.

SiC substrate can have microscopic defects, such as Threading Screw Dislocation (TSD), Threading Edge Dislocation (TED), Base Plane Dislocation (BPD), and others. These defects are caused by deviations in the arrangement of atoms at the atomic level.

Within the silicon carbide (SiC) industry chain, substrate suppliers hold significant leverage, primarily due to value distribution. SiC substrates account for 47% of the total value, followed by epitaxial layers at 23%, while device design and manufacturing constitute the remaining 30%. This inverted value chain stems from the high technological barriers inherent to substrate and epitaxial layer production. Three major challenges plague SiC substrate growth: stringent growth conditions, slow growth rates, and demanding crystallographic requirements. These complexities contribute to increased processing difficulty, ultimately resulting in low product yields and high costs. Furthermore, the epitaxial layer’s thickness and doping concentration are critical parameters directly impacting the final device performance.

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.

SiC substrate can have microscopic defects, such as Threading Screw Dislocation (TSD), Threading Edge Dislocation (TED), Base Plane Dislocation (BPD), and others. These defects are caused by deviations in the arrangement of atoms at the atomic level. SiC crystals may also have macroscopic dislocations, like Si or C inclusions, micropipe, hexagonal voids, polymorphs, etc. These dislocations are typically large in size.

The process of isostatic graphite manufacturing is Selecting raw materials, Blending, Molding, Isostatic pressing, Carbonization, Graphitization.