Description
The ppm-level electrolytic moisture analyzer is a high-end analytical instrument purpose-built for semiconductor gas delivery lines and highly acidic, corrosive processing environments. Harnessing the intense hygroscopicity of phosphorus pentoxide P2O5 and operating under Faraday's Law, the sensor converts trace water down to 0.01ppm directly into a proportional electrolytic current, achieving drift-free, calibration-free measurement. Equipped with chemically inert platinum or gold electrodes, it is highly resilient against harsh, acidic semiconductor specialty gases (such as HCl, Cl2, and HBr). It continuously monitors trace moisture to prevent critical wafer contamination and to stop the formation of devastating, water-induced acidic corrosion in stainless steel manifolds, securing tool uptime and process yield. (Note: Due to its acidic sensing chemistry, this technology is strictly prohibited for alkaline gases like NH3).
Principle
Trace moisture H2O) in the gas is 100% absorbed by a highly hygroscopic P2O5 film on inert Pt/Au electrodes. An applied DC voltage continuously electrolyzes this absorbed water into hydrogen (H2) and oxygen (O2). According to Faraday's Law, the resulting electrolysis current is directly and linearly proportional to the absolute moisture concentration, providing a drift-free, calibration-free measurement.
Application
• Acidic Semiconductor Specialty Gases (UHP ESG) [ppm Range]
Hydrogen Chloride (HCl ) & Chlorine (Cl2) Gas Lines: Critical moisture defense in aluminum and metal etching loops. While dry "HCl" is non-corrosive, even 1 "ppm" of moisture triggers instantaneous hydrochloric acid formation, which aggressively corrodes stainless steel tubes and gas boxes.
Hydrogen Bromide (HBr ) & Boron Trichloride (BCl3): Monitoring trace water in silicon gate-stack etching processes to prevent catastrophic acid pitting on expensive mass flow controllers (MFCs) and pneumatic valves.
Sulfur Hexafluoride (SF6) etching gas: Measuring incoming gas moisture to ensure pristine plasma etching chemistry.
• Semiconductor UHP Bulk Gas & Purging Systems [ppb/ppm Range]
Epitaxial & CVD Nitrogen/Argon Purge Gas: Delivering calibration-free, ultra-precise monitoring of bulk inert gases to guarantee sub-ppm moisture levels before gases enter chemical vapor deposition (CVD) or epitaxial growth chambers.
Load-lock Chamber Venting: Tracking the purge efficiency of load-locks during substrate entry. The analyzer ensures ambient moisture adsorbed on wafer cassettes is fully desiccated prior to high-vacuum processing.
• Chemical & Petrochemical Chlorination Processes
Chlor-Alkali Chlorine Gas Drying: Controlling drying towers in chlorine liquefaction plants. The P2O5 sensor verifies the dry status of chlorine gas to prevent catastrophic downstream pipeline failure.
Phosgene Gas Synthesis: In-line moisture tracking in highly toxic phosgene streams, where trace moisture destroys the reactant balance and leads to severe corrosion in reactors.
• High-Purity Gas Cylinder Charging & Specialty Gas Plants
Electronic-Grade Gas Bottling: Used as the master reference instrument at gas filling stations to certify ultra-dry cylinders of reactive or acid-forming electronic specialty gases.
Measurement components and ranges
• H2O: 0~1ppm/10ppm/100ppm/500ppm(Max.2500ppm)
For detailed introduction, please refer to Trace Mositure Analyzer.