We provide technical expertise in identifying and controlling Airborne Molecular Contamination (AMC) and Surface Molecular Contamination (SMC) for improving process and product yields for semiconductor, photovoltaic, LED, lasers, optoelectronics, disk drives, and other contamination-sensitive industries.
Sample Types
- Cleanroom air
- Clean dry air (CDA)
- Ultrapure nitrogen (HPN2)
- Silicon wafers
- Clean benches
- Tool cabinets
- Flooring
- Electrostatic chucks
- Tool stages
Analyses and Services Provided
Analyses
- Trace metals
- Dopants ( B,P, As, Sb )
- Organics, including refractory organics
- Other special tests as need when fabs have new or unique technologies (failure analysis, leaches of hazed optics, particle ID, wipe studies…
Services
- Baselining via grab sampling in critical process and manufacturing areas
- Trouble shooting and resolving contamination escalations
Techniques
Sampling
- Bubbler / impinger method
- Organic adsorption sampler
Analytical
- Inductively coupled plasma mass spectrometry (ICP-MS)
- Ion chromatography (IC)
- Ion chromatography mass spectrometry (IC-MS)
- Full wafer TD GC-MS
Lithography Concerns
Selective Issues
- AMC can form hazing (surface contamination) on optics
- NH3 is typically present at “high” concentrations in lithography areas
- Presence of Cl- or SOx can deposit on optics
- Silicon-containing materials can outgas and leave SiO2 on optics
Recommended Tests
- AMC in stepper (before and after filters)
- AMC in room
- N2, CDA testing (before and after purifiers)
- Mask, wafer and other storage area (compacts and stockers)
- Wafers or substrates exposed to FOUP’s, Pods, compacts, shippers
Industry Guidelines
- ITRS ( International Technology Roadmap for Semiconductors)
- ISO 16444-8