【What is SiC (silicon carbide)】

Silicon carbide (SiC) is a ceramic material with excellent heat resistance and chemical resistance, and has the second highest hardness after diamond and boron carbide (new Mohs hardness: diamond = 15, silicon carbide = 13).
It has a crystal structure similar to that of diamond, and its high hardness is maintained by strong covalent bonds, making it difficult for its mechanical strength to deteriorate even under high temperatures. For this reason, the melting point of silicon carbide exceeds 2,500°C, and it is also used as a material for channels through which molten iron flows.

【Features of SiC (Silicon Carbide) Screws】

The main features of SiC (silicon carbide) screws (NBK product number: SICX) are heat resistance and chemical resistance.
The heat resistance allows operation at temperatures around 1500°C, and the small coefficient of linear expansion helps mitigate the impact of thermal expansion on the screws.
Chemical resistance withstands highly corrosive substances essential in semiconductor manufacturing, including "ammonia water," "hydrogen peroxide water," "hydrofluoric acid," and "SPM."

【SICX Product Page】

Click here for product information such as screw diameter, screw length, and tightening torque.

【SICX Usage】

As semiconductor devices become smaller and more advanced, the chemicals (wafer cleaning solutions, etc.) used in the cleaning process are becoming more corrosive than ever before.
Wafer processing temperatures are also becoming higher, requiring screws with higher heat resistance.
SICX is effective for equipment that uses these highly corrosive chemicals and in high temperature environments.

Application Examples

・Wafer Cleaning Equipment

・Equipment that generates high internal temperatures (ion implanter, light source for lithography equipment, deposition equipment, etching equipment, etc.)

【SICX Characteristics】

Physical Properties
Specific Gravity (g/cm3)	3.12
Volume Resistivity (Ω・m)	0.2~1.8×10-1
Thermal Conductivity (W/(m・k))	153
Linear Expansion Coefficient (K-1)	4.3×10-6
Vickers Hardness (GPa)	22(21.7)
Water Absorption Rate	less than 0.1
Young's Modulus (GPa)	402
3-point Bending Test (MPa)	470

Chemical Name	Temperature	Effect
Ammonia (28.0～30.0％)	Room Temperature	◎
Hydrogen peroxide solution (30.0～35.5％)	Room Temperature	◎
Hydrofluoric Acid (49.5～50.5％)	Room Temperature	◎
50％ sulfuric acid	Room Temperature	◎

• ◎：No Corrosion
• 〇：Slight Corrosion
• △：Moderate Corrosion
• ×：Heavy Corrosion

※The values are not for SICX (SiC screw) but for SiC material. These are general values, not guaranteed values.