China high-density graphite Manufacturers, Suppliers, Factory

A P-type silicon carbide (SiC) wafer is a semiconductor substrate that is doped with impurities to create a P-type (positive) conductivity. Silicon carbide is a wide-bandgap semiconductor material that offers exceptional electrical and thermal properties, making it suitable for high-power and high-temperature electronic devices.

As the core material of the third-generation semiconductors, silicon carbide (SiC) is playing an increasingly important role in high-tech fields such as new energy vehicles, photovoltaic energy storage, and 5G communications due to its excellent physical properties.

In the high voltage field, particularly for high-voltage devices above 20,000V, the SiC epitaxial technology still faces several challenges. One of the main difficulties is achieving high uniformity, thickness, and doping concentration in the epitaxial layer. For the fabrication of such high-voltage devices, a 200um thick silicon carbide epitaxial wafer with excellent uniformity and concentration is required.

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.

Defect-free epitaxial growth occurs when one crystal lattice has nearly identical lattice constants to another. Growth happens when lattice sites of the two lattices at the interface region are approximately matched, which is possible with a small lattice mismatch (less than 0.1%). This approximate matching is achieved even with elastic strain at the interface, where each atom is slightly displaced from its original position in the boundary layer. While a small amount of strain is tolerable for thin layers and even desirable for quantum well lasers, the strain energy stored in the crystal is generally lowered by the formation of misfit dislocations, which involve a missing row of atoms in one lattice.

The third-generation wide bandgap semiconductor materials, such as Gallium Nitride (GaN) and Silicon Carbide (SiC), are renowned for their exceptional optoelectronic conversion and microwave signal transmission capabilities. These materials meet the demanding requirements of high-frequency, high-temperature, high-power, and radiation-resistant electronic devices. Therefore, they have vast application prospects in new-generation mobile communications, new energy vehicles, smart grids, and LED technologies. The comprehensive development of the third-generation semiconductor industry urgently requires breakthroughs in key core technologies, continual advancement in device design and innovation, and a resolution to import dependencies.