Applications
Semiconductor Wafer Fabrication
Fused quartz, sapphire, and technical ceramic components for diffusion, CVD, plasma etch, CMP, and wet cleaning processes in silicon wafer manufacturing.
Fused Quartz & Ceramics in Semiconductor Wafer Fabrication
Silicon wafer fabrication (the “front end” of semiconductor manufacturing) requires process components that survive extreme temperatures, aggressive chemistries, and plasma environments while contributing zero contamination to the silicon wafer. Fused quartz, sapphire, and technical ceramics are the only materials that meet these requirements.
Process-by-Process Component Guide
Thermal Oxidation & Diffusion (600–1200°C)
The oldest and most established semiconductor processes — growing SiO₂ on silicon or diffusing dopants (B, P, As) — use horizontal or vertical furnaces lined with quartz hardware.
| Component | Material | Function |
|---|---|---|
| Process tube (inner) | Synthetic fused silica Grade 2 | Reaction chamber; zero metal contamination |
| Process tube (outer) | Natural fused quartz Grade 1 | Thermal isolation |
| Wafer boat | Fused quartz Grade 1 or 2 | Holds wafers at pitch ±0.1 mm |
| Baffles | Fused quartz Grade 1 / Opaque Grade 3 | Gas flow conditioning |
| Push rod | Fused quartz Grade 1 | Boat loading/unloading |
| Flange | Fused quartz Grade 1 | Tube-to-furnace interface |
Low-Pressure CVD (LPCVD)
LPCVD deposits thin films (poly-Si, SiO₂, Si₃N₄, WSi₂) at 600–900°C and pressures of 0.1–10 Torr. The deposition environment is corrosive to metals and requires ultra-low contamination quartz hardware.
| Component | Material | Key Requirement |
|---|---|---|
| Reactor tube | Synthetic fused silica Grade 2 | < 50 ppb total metals; polished inner bore |
| Gas injector | Synthetic fused silica Grade 2 | Precise hole array ±0.02 mm; He leak < 10⁻⁹ |
| Wafer boat | Synthetic fused silica Grade 2 | Slot pitch ±0.1 mm; no SiC or ceramic contamination |
| Viewport window | Fused quartz or sapphire | In-situ monitoring |
Plasma Etch (RIE, ICP, CCP)
Reactive plasma etching (fluorine, chlorine, bromine chemistry) operates at room temperature but subjects chamber hardware to intense ion bombardment. Quartz is preferred for its self-passivating behavior in fluorine plasma.
| Component | Material | Why |
|---|---|---|
| Focus ring / edge ring | Fused quartz Grade 1 | Self-limiting fluorine attack; low contamination |
| Dome / liner | Fused quartz Grade 1 | Plasma-facing enclosure |
| Viewport | Sapphire | Superior plasma erosion resistance vs. quartz |
| Chamber liner | Alumina 99.5% | Longer life in Cl₂/Br₂ chemistry than quartz |
Wet Cleaning (HF, RCA, Piranha)
Wet chemical cleaning removes particles, organics, and metals from wafer surfaces before and after deposition steps.
| Component | Material | Chemistry Handled |
|---|---|---|
| Cleaning tank | Fused quartz Grade 1 | HF, BHF, SC-1, SC-2, Piranha |
| Overflow tank | Fused quartz Grade 1 | DI water rinse |
| Gas sparger | Fused quartz Grade 1 | O₃, N₂ bubbling |
| Wafer cassette | Fused quartz or alumina | Part carrier in chemical bath |
Rapid Thermal Processing (RTP)
RTP systems heat a single wafer from room temperature to > 1000°C in seconds using tungsten-halogen or arc lamps. The transparent quartz or SiC reactor dome must transmit radiant energy and survive thermal shock.
| Component | Material | Key Requirement |
|---|---|---|
| Process dome | Fused quartz Grade 2 | High UV-VIS-NIR transmission; < 10 nm/cm birefringence |
| SiC susceptor | Reaction-bonded SiC | ΔT > 400°C thermal shock; 1380°C continuous |
| Pyrometry window | Sapphire | Mid-IR transparency for temperature measurement |
| Quartz window | Synthetic fused silica | Lamp-to-process zone light transmission |
Why Tuguan for Semiconductor Components?
- Dedicated quartz-only machining cells — no metallic cross-contamination
- ISO Class 7 cleanroom for final cleaning and inspection
- Grade 2 synthetic silica (< 50 ppb metals) stocked in standard tube, rod, and plate formats
- Full QC package — CMM + Ra + He leak + ICP-OES available on every shipment
- Replacement parts program — OEM-compatible focus rings, boats, and tubes to drawing