Chemical Blend and Dispense Unit

Fäth Chemical Blend and Dispense Unit is a product of avant-garde technology and modern engineering that supplies consistently high-quality homogeneous blends of liquid chemicals at a push of a button. The system utilizes enhanced weight measurement and control applications capable of delivering high-precision data from milligrams to tons. This system enables complex filling and blending of up to 6 different process chemicals. The PID controller enables efficient and automatic control of the pumps’ input speed with feedback pressure in the loop. This ensures that the dispense pressure is always maintained to facilitate the high demands of wafer fabrication process tools at any given time. The metrology system utilizes digital refractometers to monitor the consistency of concentrations with explicit accuracy via optical measurements of the liquid chemicals’ refractive index and temperature in real-time, ensuring high process efficiency and reliability.

The equipment design considerations span several areas, including conforming to regulatory requirements to consistently meet operating objectives, occupational health, and safety standards. The system is controlled using the integration of PLC and HMI to facilitate fully automatic operations that require minimal user intervention while providing the user with a visual overview of the system’s status at a glance. Various safety features are incorporated into the system to detect hazards and perform necessary functions automatically to mitigate accidents.

Kindly consult Fäth Asia for assistance in developing a system that meets your technical and commercial requirements.

Standard Features

  • Fully-automated pump switchover function for uninterrupted chemical delivery
  • Automatic system shutdown from hardware safety interlocks
  • Automatic batch mixing, batch release, and batch disposal
  • Automatic chemical quality analysis before batch release (offline metrology)
  • Automatic chemical quality analysis during delivery (online metrology)
  • Configurable sequence and the recipe for mixing
  • Weight monitoring for mixing
  • Enclosure for mixing tank
  • Loop pressure monitoring and control to ensure constant pressure at the point of use
  • Optimal piping layout and design
  • Centrifugal pump for high-flow applications
  • Redundant pumps and filters
  • Automatic pump and filter priming
  • Automatic system flushing and purging
  • Differential pressure monitoring across filters
  • N2 for drum or tote blanketing
  • UPW or UN2 spray gun
  • Auxiliary media pressure sensors for pneumatic system

System Control

  • Siemens SIMATIC S7 series PLC
  • Siemens SIMATIC Comfort Panel HMI
  • User authorisation and password protection HMI
  • Multilingual operational guide on HMI
  • Manual actuation of pneumatic valves
  • Linkage to supervisory control and data acquisition (SCADA) system for remote system monitoring and control

Safety Features

  • Isolated process and electrical enclosures
  • CDA-purge function for electrical enclosure
  • Audible and visual alarms and warnings
  • Local and remote EMO
  • Exhaust flow detection
  • Cabinet leak detection
  • Utility service leak detection
  • Door interlock system
  • Failure Modes and Effects Analysis (FMEA)


  • Diaphragm pump with pulsation dampeners, stroke counter, and leak detection
  • Fab-wide chemical recirculation with temperature monitoring and control
  • Manual batch mixing, batch release, and batch disposal
  • Flow monitoring of process chemicals for mixing
  • Mixing tank capacity up to 800 L
  • Pressure and flow monitoring at the pump outlet
  • Loop consumption monitoring
  • FM4910 Fire Retardant Plastics enclosure
  • Manual maintenance services

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