Expert Solutions Purity & Specialty Issue 21 | Page 8

KEY APPLICATIONS COULOMETRIC SENSING PROVIDES ESSENTIAL TRACE AND ULTRA-TRACE OXYGEN MEASUREMENTS FOR MANY INDUSTRIES. WE HIGHLIGHT TWO IMPORTANT APPLICATIONS THAT RELY ON THE ACCURACY AND SENSITIVITY OF THE COULOMETRIC GAS ANALYZER. POST-PURIFIER MEASUREMENTS IN SEMICONDUCTOR WAFER MANUFACTURING COULOMETRIC OXYGEN ANALYSIS IN AIR SEPARATION PROCESSES Gases are supplied to semiconductor customers in multiple forms, including an on- site Air Separation Unit (ASU), bulk tube trailers and bulk tanks. Nitrogen (N 2 ), oxygen (O 2 ) and argon (Ar) need to be measured as impurities at various points across the Air Separation Unit ASU process. Semiconductor companies use purifiers to ensure that only the purest gases enter the process environment. To monitor successful purification, stationary analytical systems are installed to monitor bulk gases in post-purifier locations. Typically, these contain multiple analyzers for each gas, and it is common to have between 10 and 20 analyzers per system. Each of these systems is integrated into the building management system using digital connectivity to collect and trend gas purity data. Servomex provides a trusted, complete gas analysis system for the ultra-high-purity (UHP) gases in the semiconductor industry. Oxygen (O 2 ) analysis is provided by the DF-500 range. This provides Coulometric sensing with Lower Detection Limits of 200 parts per trillion (ppt) from the DF-550E model and 45ppt from the DF-560E, delivering the best ultra-trace analysis available to the industry. In addition, mobile analytical carts are widely used by manufacturing locations to ensure the quality of specific gas line installations. This is because each new gas line in a semiconductor fab must be qualified before use in production – impurity analysis is a key parameter in this. Again, the DF-500 range provides the trace- level O 2 measurements required. When verifying the quality of Ar and N 2 product streams, O 2 analysis at parts per billion (ppb) levels is needed to ensure purity. SERVOPRO MonoExact DF310E TRACE OXYGEN Touchscreen GUI Advanced digital communications Compact footprint for simple integration FIXED RACK SYSTEM PORTABLE CART SYSTEM The analytical platform used depends on ASU plant conditions, but typically the SERVOPRO MonoExact DF310E or SERVOPRO MultiExact 4100 is configured with a Coulometric sensor for this application. O 2 Both these analyzers provide an advanced gas monitoring platform that combines the benefits of Coulometric technology with digital connectivity and intelligent processing. They are particularly applied near the end of the ASU process, before each gas reaches the product compression stage. SERVOPRO MultiExact 4100 MULTI-GAS Measures up to four gas streams simultaneously Up to 32 alarms and 32 relays Digital communications for remote access INTUITIVE GAS SOFTWARE See our solutions for wafer manufacturing: servomex.com/dfhighpurity P08 Servomex’s Coulometric sensor can readily supply these measurements, making it ideal for quality analysis of the end product. Discover our solutions across the ASU process: servomex.com/servopro P09