Alumina Ceramic, also called Al2O3 ceramic, is playing a crucial role in the semiconductor industry for its high purity, excellent electric insulation, high temperature resistance, and chemical stability. According to the statistics of the World Semiconductor Trade Statistics(WSTS) organization, Global Annual Semiconductor Sales Increase 25.6% to $791.7 Billion in 2025. The global semiconductor industry is expected to reach US$975 billion in annual sales in 2026. Advanced Ceramics are widely used in semiconductor equipment, among which,
high purity alumina ceramic holds a leading position in the semiconductor ceramic parts market, with a market share exceeding 50–60%. As a manufacturer serving the global industrial ceramics market, Mingrui Ceramics will today discuss the main applications and technical details of alumina ceramics in the semiconductor field:
Outstanding Material Properties Define the Core Strength of the Al2O3 Ceramic
High-purity alumina ceramic (Al2O3 ≥99%) has become the key material in semiconductor equipment due to its excellent properties. For example：
Dielectric Properties: The dielectric strength of Al2O3 ceramic is ≥8.7 kV/mm (for 5 mm thickness), and it can maintain stable insulation performance under high-frequency electric fields, effectively ensuring the reliable operation of equipment.
Thermal Matching Properties: With a coefficient of thermal expansion (CTE) of ≥7.7×10⁻⁶/℃, it achieves a 98% match with the thermal expansion behavior of silicon wafers, greatly reducing stress issues caused by thermal mismatch.
Mechanical Strength: Flexural strength ≥340 MPa. When used in chemical mechanical polishing (CMP) pads, its service life can exceed 5,000 hours, significantly improving production efficiency.
Main Application of Al2O3 Ceramic in Semiconductor Industry
1. Integrated Circuit (IC) Packaging Substrates
Multilayer Ceramic Substrates are typically used as ceramic insulation sheets for electrical insulation and heat-dissipation in power modules (e.g., IGBT, MOSFET), supporting the chips and providing electrical interconnections.
LED Packaging: Serves as the carrier substrate for LED chips, offering both thermal conductivity and electrical insulation.
Advantages: ① Insulation: Volume resistivity >10¹⁴ Ω·cm, effectively isolating high voltages (>1 kV). ② Thermal Conductivity: Approximately 25–30 W/(m·K); although lower than aluminum nitride (AlN, 170–200 W/(m·K)), it offers a more cost-effective solution for medium to low power applications. ③ Thermal Expansion Matching: Closely matches the coefficient of thermal expansion of silicon chips (7.6×10⁻⁶/°C), and it can reduce thermal stress. ④ High Purity: 99.9% alumina ceramic can minimize impurities, which could affect high-frequency signal performance.
2. Key Components for Semiconductor Manufacturing Equipment
Electrostatic Chuck (ESC):
Function: Secures silicon wafers during processes such as etching and thin film deposition (CVD/PVD) via electrostatic adsorption.
Requirements: High flatness (<1 μm), resistance to plasma corrosion (Cl2, CF4, etc.), and high temperature resistance (>300°C).
Advantages of Alumina: ① Surface can be machined to a mirror finish (Ra <0.01 μm) to ensure uniform wafer contact. ② Superior plasma corrosion resistance compared to metallic materials.
RF Window:
Function: Transmits microwave or radio frequency signals in plasma equipment while isolating the vacuum from the atmosphere.
Requirements: Low dielectric loss (tanδ <0.0002), high transmissivity.
Advantages of Alumina: High-purity alumina (99.9%) has a stable dielectric constant (ε ≈ 9.8) and low dielectric loss ( <0.0001), suitable for high-frequency (>1 GHz) applications.
3. Wafer Transfer and Processing Components
Robotic Arm End Effector:
Requirements: Lightweight, high rigidity, low particle release.
Alumina Advantages: Low density (3.7-3.95 g/cm³), 50% lighter than stainless steel, reducing the load on the robotic arm. Extremely low particle shedding after surface polishing, meeting cleanroom (Class 1) standards.
Vacuum Chamber Liner:
Function: Protect the chamber's metal walls from plasma corrosion.
Alumina Advantages: Superior corrosion resistance compared to quartz, which can extend equipment maintenance intervals.
4. Sensors and Insulation Components
Temperature Sensor Ceramic Protection Tube:
Function: Protect thermocouples in high-temperature processes (e.g., diffusion furnaces).
Alumina Advantages: Temperature resistance >1600°C, chemically inert, preventing contamination of the process environment.
High-Voltage Ceramic Insulating Ring:
Function: Isolates high-voltage power supplies from equipment housings (e.g., ion implanters).
Alumina Advantages: Breakdown field strength >15 kV/mm, ensuring safe equipment operation.
5. Components in Photolithography
Mask Support Structure:
Function: To fix the mask in an EUV (Extreme Ultraviolet) lithography machine, ultra-high dimensional stability is necessary.
Advantages of Alumina: Low coefficient of thermal expansion (8×10⁻⁶/°C) can reduce the impact of thermal drift on lithography accuracy.
6. New Applications: Third-Generation Semiconductor Packaging
Silicon Carbide (SiC) and Gallium Nitride (GaN) Device Packaging:
Requirements: High-reliability packaging materials are needed for high-frequency, high-temperature (>200°C) operating conditions.
Alumina Improvement Directions: Co-firing with metals (Cu, Ag) (LTCC/HTCC technology) to improve heat dissipation and current carrying capacity. Surface metallization coatings (such as Au, Ag) to optimize high-frequency signal transmission.
Alumina ceramics are widely used throughout the entire semiconductor industry chain, from manufacturing equipment to packaging components. They stand out in ceramic materials, relying on excellent electrical insulation, corrosion resistance, and cost advantages. Mingrui Ceramic has been dedicated to high-purity alumina ceramic parts ranging from 95-99.99%. If you have any requirements or urgent questions on semiconductor ceramic parts, please
reach out to us to get your tailored solutions.
