Sensitivity range: 20 - 100 nm

World's first 20 nm chemical particle counter

Leading-edge microelectronic processes require very clean process chemicals that are highly filtered and regulated to a particle size of 20 nm or below. With 20 nm particle sensitivity, the Chem 20 Chemical Particle Counter is the world's most sensitive particle sensor for high purity process chemicals.

Extensive data on chemical distribution and packaging systems proves that the Chem 20 sensor, with 20 nm sensitivity, detects larger concentrations of particles with better statistics than competitive products. The Chem 20 Chemical Particle Counter is a valuable tool that enables facility and process engineers to quickly detect and characterize chemical particle sources before they impact process and device performance.

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  • Advanced laser optics and detectors enable 20 nm sensitivity in chemicals
  • On-board chemical flow meter to set sample flow
  • First particle counter optimized for low and high refractive index chemicals for improved performance:
    • Chem 20 sensor, for chemicals with lower indices of refraction
    • Chem 20-HI sensor, tailored for sulfuric acid and other higher-index chemicals
  • On-board leak detection to provide alarm upon an internal chemical leak
  • Low-flow detector and alarm to ensure consistent data
  • Bubble detector to optimize data and protect sensor
  • Local data display


  • Detect 20 nm PSL & 9 nm Au particles in real time
  • Detect yield-limiting particles (not possible with competitive technologies)
  • React quickly to particle excursions long before surface scan or yield data are available
  • Optimize chemical delivery systems from the loading dock to point-of-process
  • Tighten process control limits through improved sample population statistics
  • Optimize instrument operation for very dirty or very clean applications using two view modes, extending product application space
  • Support legacy data acquisition systems with flexible communications


  • Real-time particle monitoring within chemical distribution systems
  • Point-of-process monitoring
  • Chemical packaging operations monitoring
  • Chemical filter performance and efficiency characterization
  • Performance testing of chemical handling components

Available Accessories

Facility Net Software

Facility Net Software

Facility Net Software provides a solution for comprehensive environmental monitoring, including a real-time and historical data display. Compatible with Particle Measuring Systems particle counters and molecular contamination monitors, as well as various third-party products.

Liquid Installation Kit

Liquid Installation Kit

For use with online  applications, the Liquid Installation Kit includes: a Flaretek® flaring tool, five caps, 25 ft of 1/4 in Perfluoroalkoxy alkanes (PFA) tubing and male connectors.

Environmental Control Cabinet for Liquid Particle Sensors

Environmental Control Cabinet for Liquid Particle Sensors

The Environmental Control Cabinet for Chem 20TM and Ultra DI® 20 precisely controls the environmental temperature to ensure precise and consistent data. Used inside chemical distribution rooms where the ambient temperature is not well-controlled, the Environmental Control Cabinet shields the particle sensor from environmental changes that adversely impact data quality.

Bubble Separator Device

Bubble Separator Device

A welded PFA device that allows entrained bubbles in an ultrapure water (UPW) or process chemical sample to separate from the sample stream through buoyancy, prior to the sample entering the liquid particle counter.

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Still have Questions?

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