In the first place, what is SiC?

SiC (silicon carbide) is a compound of silicon and carbon discovered by Mr. Acheson in the United States at the end of the 19th century. It is said that it was discovered by chance while experimenting to make diamonds. At that time, there were no semiconductors yet, so the hard and stable SiC was used as a material for abrasives and sintering materials. It is still widely used in such applications today. As a power device, practical use progressed in the 2000s.

SiC is a compound, and the raw materials are silicon dioxide (silica) and carbon materials. Written as a chemical formula, it looks like this:

　　SiO2 + 3C = SiC + 2CO

The generated SiC is pulverized and gasified in a high-temperature furnace (approximately 2000°C). It is called the sublimation method because it utilizes the transition from a solid to a gas directly. A seed crystal of SiC is placed in the furnace, and the gasified SiC is recrystallized into the seed crystal and grows as a single crystal. When a single crystal grows, it becomes a mass of single crystal called an ingot. By slicing this ingot thinly into discs, SiC wafers are created. However, devices such as MOSFETs have not yet been made. Devices such as SBDs and MOSFETs can be created on SiC wafers by creating elements in the semiconductor manufacturing process.

Until SiC power devices

SiC power device manufacturers first design diodes and MOSFETs built on SiC. Once the performance and quality have been confirmed through evaluation and verification using a prototype device, the product becomes a manufacturable product and moves on to production.

In production, wafers are procured from SiC wafer manufacturing companies, and SiC power devices that have already been designed are manufactured on the wafers. Since many devices are made on a single wafer, they are separated one by one, individually sealed with resin, and inspected to complete the package product. Compared to Si, there are differences in temperature and time in individual processes, but the general flow is the same for SiC.

Microchip does not manufacture SiC wafers, but designs and produces SiC power devices such as MOSFETs and SBDs.
Microchip is steadily expanding its range of SiC power device products, and will continue to meet expectations for high-performance SiC power devices.