Silicon Carbide (SiC) – carborundum
Silicon carbide (SiC), also known as carborundum, is a rare compound of silicon and carbon that is usually produced synthetically, although it can be found naturally in moissanite. These coatings have very unique properties, which make them useful in a wide range of applications and an important driver of Moore’s Law.
SiC wafers are conductive and can be acceptors (p-type) or donors (n-type), depending on the application. The four primary dopants for p-type wafers are: beryllium (Be), boron (B), aluminum (Al) and gallium (Ga). N-type SiC has two primary dopants: nitrogen (N) and phosphorus (P).
Properties of Silicon Carbide:
- Performs well at high temperatures.
- Low thermal expansion. SiC wafers can handle temperatures up to 1600°C without losing strength.
- High resistance to corrosion, erosion and oxidation.
- Superior hardness properties; diamond is the only harder substance.
- Fast switching speeds, which improves miniaturization.
- Great thermal conductivity.
Silicon Carbide Deposition Process:
There are two primary ways to deposit silicon carbide: physical vapor deposition (PVD) and plasma enhanced chemical vapor deposition (PECVD).
Silicon carbide PVD is when powder silicon carbide is turned to vapor either in a high temperature vacuum or with a gaseous plasma. After vaporizing all the material, it moves to a partial or full vacuum furnace where the wafers are. Once in the furnace, the vapor settles on the substrate surface, which results in a thin carborundum layer.
To deposit SiC via PECVD, a CVD furnace exposes the wafers to plasma in order to catalyze the chemical reaction on the substrate surface.
Uses for SiC Wafers:
Due to the superior temperature, hardness and corrosion properties of silicon carbide, there are many modern applications for these wafers. Some of the most common are hybrid and electric vehicles, as well as automobile parts, smart grid power switching, inverters in green energy generation, LEDs, and many other emerging markets.
Silicon Valley Microelectronics provides SiC coatings to fit the specifications of each customer, for more information on these services or to request a quote, CONTACT SVM today.