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)
- Acids and bases (including ammonium, amines, urea, SOx)
- 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
- Witness wafers – organic and metal free
- Bubbler / impinger method
- Organic adsorption sampler
Analytical
- Inductively coupled plasma mass spectrometry (ICP-MS)
- Ion chromatography (IC)
- Ion chromatography mass spectrometry (IC-MS)
- Thermal desorption gas chromatography - mass spectrometry (TD GC-MS)
- Full wafer TD GC-MS
Lithography Concerns
Balazs is a qualified laboratory for leading OEMs. Our collaboration has led to improved specifications for optimizing optics performance and stepper environment control thereby extending the lifetime of the tool.
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 (InternationalTechnology Roadmap for Semiconductors)
- SEMI F21-1102 analysis for molecular acids, bases, condensable organics and dopants.
- IEST-RP-CC035.0, Design Considerations for Airborne Molecular Contamination Filtration Systems in Cleanrooms and Controlled Environments
- ISO 16444-8
Application Notes
- APP0354 Cleanroom Air Monitoring
- APP0355 Cleanroom SEMI F21-1102 Specification
- APP0356 Particle Counts in Ultra Pure Water
- APP0369 Bases in Air and Ultrahigh Purity Gases
- APP0384 Qualification of Lithography Tools
- APP0452 IEST Working Group and Recommended Practice Support
- APP0458 Gas Chromatography for Organic Testing