The leader in In-situ and In-line monitoring of semiconductor processes for more than 20 years


Wet Process Monitoring System

The WetRad2 is an in-line, real-time, non contact concentration meter, using dual wavelength radiometery to enable cost-efficient monitoring of wet process chemicals. With its unique dual wavelength radiometer and by using pre-selected wavelengths, the WetRad2 is optimized to monitor a specific single component within a complex chemical mix.
The WetRad2’s compact design is based on CI's renowned and reliable NTM platform which is installed in thousands of process chambers working 24/7, for the monitoring of semiconductor processes.
When integrated into a control system, the WetRad2 enables tighter process control and identifies process excursions before they affect yield. 

More information
Features & BenefitsTypical applicationsKey Specifications
  • Concentration monitoring of a specific single component in a complex mix
  • Pre-Selectable dual wavelength (UV/VIS/NIR ) for optimized performance
  • Fiber based sensor for easy installation near the point of measurement
  • High stability and repeatability by continuous measurement of internal reference signals
  • High accuracy
  • Small footprint
  • Fast measurement time
  • Maintenance free - No light source replacement required
  • Simple and durable – 365/24/7 non stop
  • Standard ¼” to ¾” Flaretek® / Nippon Pillar® fittings for easy installation (For other fitting types please consult CI)
  • Ammonia (in a mix)
  • Metal Ions in mixed acid etch
  • Citric Acid in water
  • HF (in a mix)
  • Peroxide in water
  • Water in solvents
  • TMAH in water
  • Water in IPA
  • Water in Phosphoric Acid * Other chemistries supported per request

Measurement method

Fiber-optic Dual Wavelength Radiometer

Wavelength range


Calibration method


Time per measurement

Up to 10Hz (Application dependent)

Sample conditioning

None required

Temperature compensation

Automatic and continuous

Temperature range (chemicals)

0° to 120°C

Wetted materials

Teflon, Sapphire, Kalrez


RS232 / Ethernet, Analog and digital I/O

Fiberoptic length

Up to 10m

Size [mm]

Controller: 213x100x46