air testing
Balazs NanoAnalysis provides 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.
Airborne and Surface Molecular Contamination Identification

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