FUSED QUARTZ
Quartz Focus Ring & Etch Ring
Precision-machined fused quartz focus rings, etch rings, and edge rings for plasma etching and CVD chambers — ±0.01 mm tolerance, Ra 0.1 μm surface finish.
ご要望に応じてカスタム寸法・仕様に対応します。
Quartz Focus Rings & Etch Rings
Focus rings (also called edge rings or etch rings) are precision annular quartz components that surround the wafer in plasma etch and deposition chambers. They serve multiple functions:
- Electrical focusing — shape the plasma sheath uniformity at the wafer edge
- Thermal uniformity — conduct or redistribute heat at the wafer perimeter
- Edge protection — consume plasma species at the wafer edge, protecting the chuck
- Alignment reference — locate the wafer centrally on the electrostatic chuck (ESC)
Standard Geometries
Flat Focus Ring
The simplest geometry — a flat annular disc with tight flatness and parallelism specifications.
| Wafer Size | ID (Nominal) | OD (Nominal) | Thickness | Key Tolerance |
|---|---|---|---|---|
| 6” (150 mm) | 152 mm | 220–280 mm | 3–8 mm | OD/ID ±0.02 mm |
| 8” (200 mm) | 202 mm | 280–360 mm | 3–10 mm | OD/ID ±0.02 mm |
| 12” (300 mm) | 302 mm | 380–460 mm | 4–12 mm | OD/ID ±0.02 mm |
Stepped / Profile Ring
Complex cross-section with OEM-specified step geometry for conformal fit to chamber hardware.
All stepped and profiled rings are produced from 2D drawings. Common profile features:
- Chamfered inner edge (contact with wafer edge)
- Upper step for alignment tab or locating pin
- Counterbore for mounting screw clearance
- Undercut for gas flow passage
Plasma Erosion Considerations
Quartz focus rings erode under plasma exposure. Life span depends on plasma chemistry, power, and bias:
| Process | Approximate Ring Life |
|---|---|
| Si-based etch (SF₆/C₄F₈) | 200–400 RF hours |
| Metal etch (Cl₂/BCl₃) | 100–200 RF hours |
| Oxide etch (CHF₃/CF₄) | 300–600 RF hours |
| CVD (SiH₄/TEOS) | 500–1000 hours |
Tuguan Semiconductor supplies compatible replacement rings to OEM geometry specifications. Provide the OEM part number or drawing — we will reverse-measure and reproduce to ±0.02 mm.
Quality & Cleanliness
All focus rings are:
- Machined in dedicated quartz-only cells (no cross-contamination from metals)
- Ultrasonically cleaned in DI water + megasonic rinse
- Dried and inspected in ISO Class 7 cleanroom
- Double-bagged in ESD-safe packaging for shipment