CMP Slurry for Oxide
CAS Number: 7631-86-9
CMP (chemical mechanical planarization) slurry for oxide is a colloidal silica or ceria-based abrasive suspension used to planarize silicon dioxide and other dielectric films on semiconductor wafers. It combines mechanical abrasion with chemical dissolution to achieve global planarization required for multi-layer IC fabrication. Critical for STI, ILD, and PMD planarization in advanced logic and memory devices.
Technical Specifications
| pH | 10–11 (silica slurry) |
| abrasive | Colloidal silica or ceria, 12–100 nm |
| appearance | Milky white suspension |
| removalRate | 500–3000 Å/min (SiO₂) |
| selectivity | SiO₂:Si₃N₄ > 30:1 (STI grade) |
| solidsContent | 5–30 wt% |
Applications
- Shallow trench isolation (STI) planarization
- Interlayer dielectric (ILD) planarization
- Pre-metal dielectric (PMD) polishing
- BPSG and TEOS oxide planarization
- 3D NAND and DRAM dielectric CMP
Key Features
- High oxide removal rate with excellent planarity
- High selectivity to nitride stop layers (STI grade)
- Low defectivity — minimal scratching and contamination
- Stable dispersion with long shelf life