Vaisala K-PATENTS® Semicon Refractometer PR-33-S

A compact refractometer with an ultra pure modified PTFE flow cell body for semiconductor liquid chemical processes. Connected to the process by a ¼ — 1 inch pillar or flare fitting.

Vaisala K-PATENTS® Semicon Refractometer PR-33-S monitors the fab chemicals' concentration in cleanroom environment and in the integrated process tools (blending, clean, etch, and CMP).

The PR-33-S consists of an ultra-pure, modified PTFE flow cell body and an Ethernet cable that any standard PoE (Power-over-Ethernet) switch can use to transmit power to the sensor and data to a computer. The PR-33-S monitors chemical concentrations in real-time and provides an Ethernet output signal and immediate feedback, if the chemical is out of specifications. For example, low and high concentration alarms may be configured to control and increase bath life. The concentration is determined by making an optical measurement of the solution’s Refractive Index nD and temperature.

The PR-33-S is mounted directly in-line with a flare or pillar fitting. The PR-33-S has a compact, metal-free construction and it only needs a small footprint area.

Key elements:

  • N.I.S.T. traceable calibration, verification with standard R.I. liquids and validated procedure.
  • Patented CORE-optics (US Patent No. US6067151). 
  • Remote panel via Ethernet for data-logging and remote operation.
  • The communication is built by the standard UDP/IP protocols.
  • Process temperature range: -20°C – 85°C (-4°F – 185°F).
  • Fast process temperature measurement by built-in Pt1000 and automatic digital temperature compensation.

Key benefits

Completely digital device

Vaisala K‑PATENTS® Semicon Refractometer PR-33-S is used for process control and monitoring, and it provides a continuous Ethernet output signal. Compact design, and device is mounted directly in-line.

Accurate and stable measurements over the full range

Full measurement range of Refractive Index nD 1.3200–1.5300, which corresponds to 0-100 % by weight. Optional range nD 1.2600–1.4700 for strong HF. Typical accuracy R.I.+ 0.0002, which typically corresponds to 0.1% by weight, e.g. for HCl in water.

Measurement is not influenced by particles, bubbles, turbulent flow or impurities in the PPM range.

Easy maintenance

No drift. No re-calibration. No mechanical adjustments.

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