Application
of precision ceramics in semiconductor
Semiconductor devices require a large number of precision ceramic components. Because ceramics have the advantages of high hardness, high elastic modulus, high wear resistance, high insulation, corrosion resistance, low expansion, etc., it can be used as parts of silicon polishing machine, epitaxial/oxidation/diffusion heat treatment equipment, lithography machine, deposition equipment, semiconductor etching equipment, ion implantation machine and other equipment. Semiconductor ceramics include alumina, silicon nitride, aluminum nitride, silicon carbide, etc. In semiconductor equipment, the value of precision ceramics accounts for about 16%.
1. alumina (Al2O3)
Alumina is the most widely used precision ceramic material in semiconductor equipment. It has the advantages of stable material structure, high mechanical strength, high hardness, high melting point, corrosion resistance, excellent chemical stability, large resistivity, good electrical insulation, etc., and is widely used in semiconductor equipment. In semiconductor etching equipment, the etching machine chamber material is the main source of wafer pollution, and the influence of plasma etching on it determines the yield, quality and stability of the wafer etching process. Therefore, the selection of chamber materials of the etching machine is particularly important. At present, high-purity Al2O3 coating or Al2O3 ceramics are mainly used as protective materials for etching cavities and internal components. In addition to the cavity, the gas nozzles of the plasma equipment, the gas distribution plates and the fixing rings of the wafers are also required to use alumina ceramics. In the handling of wafer silicon wafers, ceramic mechanical arms made of alumina ceramics are applied. Alumina ceramics and silicon carbide ceramics have dense, high hardness, high wear resistance of physical properties, as well as good heat resistance, excellent mechanical strength, high temperature environment still has good insulation, good corrosion resistance and other physical properties, is used to make semiconductor
equipment mechanical arm of the excellent material. From the point of view of material properties, silicon carbide ceramics are more suitable for making ceramic robotic arms, but from the economic aspects of material price, processing difficulty, etc., alumina ceramic robotic arms are more cost-effective. In addition, in the wafer polishing process, alumina ceramics can be widely used in polishing plates, polishing pad correction platforms, vacuum suction cups, etc.
2. Silicon carbide (SiC)
Silicon carbide has the characteristics of high thermal conductivity, high temperature mechanical strength, high stiffness, low thermal expansion coefficient, good thermal uniformity, corrosion resistance, abrasion resistance and so on. Silicon carbide can maintain good strength at extreme temperatures of up to 1400 ° C. The grinding disk using silicon carbide ceramic has low wear due to high hardness, and the thermal expansion coefficient is basically the same as that of silicon wafer, so it can be grinded and polished at high speed. In the production of silicon wafers, it is necessary to undergo high temperature heat treatment, often use silicon carbide jig transport, its heat resistance, non-destructive, can be coated on the surface of the diamond-like (DLC) coating, can enhance performance, alleviate wafer damage, while preventing the spread of pollution. In addition, SIC ceramics can also be used in XY platforms, bases, focusing rings, polishing plates, wafer clamps, vacuum suckers, handling arms, furnace tubes, crystal boats, cantilever paddles, etc.
3. aluminum nitride (AlN)
High purity aluminum nitride ceramics have excellent thermal conductivity, heat resistance, insulation, thermal expansion coefficient close to silicon, and has excellent plasma resistance, uniform product heat distribution. Can be used in chip heating heater, electrostatic clamp, etc.
4. Silicon nitride (Si3N4)
Silicon nitride (Si3N4) is a material with high fracture toughness, strong heat shock resistance, high abrasion resistance,
high mechanical strength and corrosion resistance. Can be applied to semiconductor equipment platform, bearings and other components.
