Surface Prep (Wet)
Process Overview
Wet processing involves chemical treatments for cleaning, etching, and surface preparation. Think of it as a sophisticated chemical washing system for wafers.
Equipment Types
1
### Process Overview
Wet processing involves chemical treatments for cleaning, etching, and surface preparation. Think of it as a sophisticated chemical washing system for wafers.
### Equipment Types
#### 1. Single Wafer Tools
- Manufacturers:
- Screen (SU-3300)
- Tokyo Electron (CELLESTA™)
- SEMES
- Cost: $2-4 million
- Throughput: 200-300 wafers/hour
#### 2. Batch Systems
- Manufacturers:
- Screen
- ClassOne Technology
- RENA
- Cost: $1-3 million
- Capacity: 25-50 wafers/batch
#### 3. Spin Rinse Dryers
- Manufacturers:
- Veeco
- ClassOne
- Cost: $300,000-800,000
- Applications: Final rinse/dry
### Chemical Systems
#### Standard Clean Solutions
1. SC1 (APM)
- NH4OH:H2O2:H2O
- Cost: $5-10/liter
- Usage: Particle removal
2. SC2 (HPM)
- HCl:H2O2:H2O
- Cost: $4-8/liter
- Usage: Metal removal
3. SPM (Piranha)
- H2SO4:H2O2
- Cost: $3-7/liter
- Usage: Organic removal
#### Chemical Suppliers
- BASF
- KMG Chemicals
- Avantor
- Annual cost: $2-5 million/fab
### Facility Requirements
#### Chemical Distribution
- Chemical supply systems
- Day tanks
- Distribution piping
- Cost: $1-3 million
#### Waste Treatment
- Neutralization systems
- Metal recovery
- Water recycling
- Cost: $2-4 million
#### Safety Systems
- Chemical detection
- Ventilation
- Emergency shower/eyewash
- Cost: $500,000-1 million
### Technical Parameters
#### Process Specifications
- Temperature range: 20-85°C
- Chemical concentration: ±0.1%
- Rinse resistivity: >17 MΩ-cm
- Particle removal: >99.9%
#### Quality Control
- Chemical analysis systems
- Particle counters
- Resistivity monitors
- Cost: $200,000-500,000
### Market Analysis
- Leaders:
- Screen (~35%)
- TEL (~25%)
- SEMES (~15%)
- Annual market: ~$1.5B
- Growth: 10-15%/year
### Chemical Management
#### Storage Systems
- Bulk storage tanks
- Day tanks
- Point-of-use systems
- Cost: $500,000-1.5 million
#### Mixing Systems
- In-line mixing
- Batch mixing
- Chemical monitors
- Cost: $200,000-600,000
### Technical Challenges
1. Advanced Nodes:
- Pattern collapse
- Chemical compatibility
- Surface tension control
- Drying-induced defects
2. Environmental:
- Chemical recycling
- Waste reduction
- Green chemistry
- Water conservation
### Applications
1. Pre-furnace Clean
- Organic removal
- Particle clean
- Native oxide removal
2. Post-etch Clean
- Residue removal
- Metal contamination
- Polymer strip
3. Post-CMP Clean
- Slurry removal
- Particle clean
- Surface preparation
### Future Trends
- Single-wafer processing
- Chemical recycling
- In-situ monitoring
- Green chemistry
- Waterless cleaning
### Maintenance Requirements
- Daily chemical checks
- Weekly PM
- Monthly deep clean
- Annual cost: $150,000-300,000
### Cost Analysis
1. Operating Costs
- Chemicals: $10-20/wafer
- DI water: $5-10/wafer
- Waste treatment: $3-8/wafer
2. Infrastructure
- Chemical delivery: $2-5 million
- Waste treatment: $3-6 million
- Safety systems: $1-2 million
By Eduarda Ferreira