High Purity Alumina Polishing Plate Benefits
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Dimensional stability under wafer load
High flexural strength and elastic modulus help the high purity alumina polishing plate maintain global flatness and local planarity when carriers and pads apply pressure on 150–300 mm wafers. This reduces thickness variation and edge roll-off across the batch, even after long CMP or lapping campaigns. -
Wear resistance in abrasive chemistries
The high hardness and dense microstructure of alumina give the polishing plate a slow, predictable wear rate when working with silica, alumina or diamond slurries. This allows longer pad and plate life between refurbishing steps and helps keep the removal rate drift under control. -
Low contamination of the wafer surface
High purity Al₂O₃ and a controlled surface finish minimise metallic contamination and loose particles from the plate itself. This supports defect control on sensitive device wafers and reduces the risk of adding particles that would otherwise show up as scratches or embedded defects. -
Customizable geometry for different tools
Outer and inner diameters, ring width, groove layout, back-side pockets and mounting features can be defined according to each CMP or lapping tool. This makes it easier to retrofit existing polishers, wafer reclaim tools and pilot lines without redesigning the whole platform. -
Compatibility with multiple substrate types
The same high purity alumina polishing plate concept can be adapted for silicon, SiC, sapphire, glass and advanced ceramic substrates by adjusting pad type, groove pattern and slurry chemistry. One plate family can therefore support several process recipes across different product lines.
High Purity Alumina Ceramic Polishing Plate Properties
| Property | Unit | 99.5% Al₂O₃ | 99.6% Al₂O₃ | 99.7% Al₂O₃ | 99.8% Al₂O₃ | 99.9% Al₂O₃ | 99.99% Al₂O₃ |
| Alumina content | % | 99.5 | 99.6 | 99.7 | 99.8 | 99.9 | 99.99 |
| Density | g/cm³ | 3.89 | 3.91 | 3.92 | 3.93 | 3.94 | 3.98 |
| Open porosity | % | 0 | – | – | – | – | – |
| Color | – | Ivory | Ivory | Ivory | Ivory | Ivory | Ivory |
| Water absorption | % | – | 0 | 0 | 0 | 0 | 0 |
| Young’s modulus (Elastic modulus) | GPa | 375 | 356 | 357 | 358 | 359 | 362 |
| Shear modulus | GPa | 152 | – | – | – | – | – |
| Bulk modulus | GPa | 228 | – | – | – | – | – |
| Poisson’s ratio | – | 0.22 | – | – | – | – | – |
| Compressive strength | MPa | 2600 | 2552 | 2554 | 2556 | 2558 | 2570 |
| Flexural strength | MPa | 379 | 312 | 313 | 314 | 315 | 320 |
| Fracture toughness | MPa·m¹ᐟ² | 4 | – | – | – | – | – |
| Hardness | GPa | 14.1 (≈1440 kg/mm²) | 23 | 24 | 25 | 26 | 30 |
| Thermal conductivity | W/m·K | 35 | 32–37 | 33–38 | 34–39 | 35–40 | 36–42 |
| Thermal shock resistance ΔT | °C | – | 222 | 223 | 224 | 225 | 228 |
| Maximum use temperature (no load) | °C | ≤1750 | 1755 | 1760 | 1765 | 1770 | 1800 |
| Coefficient of thermal expansion | 10⁻⁶/°C | 8.4 | – | – | – | – | – |
| Specific heat | J/kg·K | 880 | – | – | – | – | – |
| Volume resistivity | Ω·cm | >1×10¹⁴ | >1×10¹⁴ | >1×10¹⁴ | >1×10¹⁴ | >1×10¹⁴ | >1×10¹⁴ |
| Dielectric constant (relative permittivity) | – | 9.8 | 9.83 | 9.84 | 9.85 | 9.86 | 9.92 |
| Dielectric strength | kV/mm | 16.9 | 23.2 | 23.4 | 23.6 | 23.8 | 24 |
| Dissipation factor (loss factor @ 1 kHz) | – | 0.0002 | – | – | – | – | – |
High Purity Alumina Polishing Plate Specification
| High Purity Alumina Polishing Plate | ||
| Item No. | Diameter (mm) | Thickness (mm) |
| AT-HP-PT01 | Customize | |
High Purity Alumina Polishing Plate Packaging
- Each high purity alumina ceramic grinding disc is placed in a custom foam or soft-pad tray that supports the full surface and edges to minimise impact and chipping.
