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Real-time Particle Detection in Semiconductor Vacuum Environment

Technology #z04142

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Semiconductor WaferParticle Detection
David Pui, PhD
Professor, Mechanical Engineering, College of Science and Engineering
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Yi Liu
Researcher, College of Science and Engineering
Christof Asbach
Oberhausen, Germany
Heinz Fissan
Kerken-Aledekerk, Germany
Managed By
Kevin Nickels
Technology Licensing Officer 612-625-7289
Patent Protection
US Patent 7,655,945

Metal and Non-metal Particles can be Monitored

A particle-detecting integrated circuit that contains a device with a pair of conductive lines positioned in a vacuum environment can detect particles in real time in a semiconductor vacuum environment. The conductive lines are spaced at a critical pitch corresponding to diameters of particles of interest. An impedance measurement system linked to the circuit detects a change in an electrical property (e.g., a short in a current flow or a change in capacitance) of the conductive lines when a particle becomes lodged between the lines (particles smaller than the size of the pitch) or bridges the gap in-between (particles larger than the size of the pitch). A metallic particle larger than the pitch size generates a short in a current flow between the lines, while a non-metallic particle generates a change in capacitance between the lines.


  • Detects particles in real time in a semiconductor vacuum environment
  • Detects changes in an electrical property
  • Monitors metallic or non-metallic particles


  • Photolithography
  • Depositing film on semiconductor wafers
  • Dopant implanting on semiconductor wafers

Phase of Development - Proof of Concept