Given the critical nature of semiconductor cleanrooms, I should emphasize precision contamination control. Particle size matters here - we're talking sub-micron levels. The user didn't specify wafer size or process type, but 300mm fabs would be the modern standard.
1. Objective:
Design a high-reliability, ultra-clean centralized vacuum system for ISO Class 5-7 semiconductor fabrication areas, ensuring particle control below 0.1μm, ESD safety, chemical compatibility, and minimal vibration.
2. System Architecture:
✅ Centralized System:
Primary vacuum pump (Oil-free dry claw/scroll type: 15–25 kW, 150–250 m³/h flow)
Redundant backup pump with auto-failover
Buffer tank (500–1,000L) with pressure stabilization
✅ Distribution Network:
Electropolished 316L stainless steel piping (DN50–DN80)
Conductive PTFE/PFA tubing at tool connections
Zoned valving for process tool isolation
✅ Filtration Stages:
Pre-filter (Tool-side): 99% @ 1μm (Bag/cyclonic)
Primary HEPA: 99.97% @ 0.3μm
Final ULPA: 99.9995% @ 0.12μm
Redundant exhaust safety filter
3. Critical Design Parameters:
Parameter Specification
Operating Pressure -60 to -70 kPa (adjustable zones)
Particle Control ≤ 0.1 particles/ft³ @ 0.1μm
Air Velocity 20–25 m/s (main headers)
Leak Rate < 1% system volume/hour
Noise Level ≤ 65 dBA at 1m
ESD Protection < 10⁹ Ω surface resistivity
4. Process-Specific Safety:
⚡ Chemical Compatibility:
Perfluoroelastomer seals for etch/diffusion areas
Acid-resistant coatings on wafers handling zones
Dedicated filters for metal-containing residues
⚡ Explosion Protection:
ATEX-rated components in solvent zones
Nitrogen purge capability
5. Monitoring & Control:
📊 SCADA Integration:
Real-time particle counters (upstream/downstream filters)
Differential pressure sensors across filters
Vibration monitoring on pumps
Flow meters per zone with auto-leak detection
Predictive maintenance alerts
6. Validation Protocol:
🔬 IQ/OQ Documentation:
IEST-RP-CC034.1 compliance testing
24-hour particle count stability test
Helium leak check (≤ 1×10⁻⁹ mbar·L/s)
Recovery test (< 1 min to ISO Class 5 after disturbance)
7. Maintenance Strategy:
🛠️ Features:
Tool-side quick-disconnect wafers
Filter change ports with containment bags
Vibration-isolated pump skid (NEMA 12 enclosure)
Annual recertification per SEMI S2/S8
8. Cost-Benefit Analysis:
Upfront Cost: $120K–$250K (500m² cleanroom)
ROI Drivers:
30% reduction in wafer defects vs. portable units
40% longer filter life through staged filtration
Elimination of AMC cross-contamination
This design exceeds SEMI F21-1102 standards for molecular contamination control while achieving <0.5% downtime through redundancy. Includes provisions for future expansion with modular headers and scalable pumping.
