Quality control Reliable performance is a requirement for CEDI modules in high performance microelectronics

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1 Microelectronics Perspectives in Pure Water Analytics News 2 THORNTON Leading Pure Water Analytics Exceptional Reliability is the Reason Siemens Choose Thornton The benefits of ultrapure water production using CEDI modules rather than resin-based systems are clear: consistent water quality and no chemical regenerants. In CEDI module production, for ensuring the units meet resistivity and temperature requirements, Siemens Water Technologies trust Thornton instrumentation for its performance and reliability. New CEDI technology Siemens Water Technologies have introduced an innovative new Continuous Electrodeionization (CEDI) platform for microelectronics, with their VNX E and EX modules. The modules are designed with new technology that allows for continuous production of ultrapure water to meet the demanding challenges of microelectronics polish and make-up water. The modular high flow components can be linked like building blocks to create highly effective pure water systems while reducing the overall water system footprint in a fabrication plant. Maintaining water quality Consistent product water quality using CEDI technology has a significant advantage over regenerable resin-based deionization. A regenerable batch DI process must be monitored for water quality degradation. Should degredation occur, additional DI vessels that have been properly regenerated and rinsed are then brought online. This leads to fluctuating water quality as can be seen with MBDI systems. CEDI-based systems, however, are continuously maintained using electrical current to drive ions, so water quality performance is highly regulated. Quality control Reliable performance is a requirement for CEDI modules in high performance microelectronics makeup water. Since 2000, Siemens has relied on Mettler-Toledo Thornton 770MAX multi-parameter, multi-channel transmitters to maintain

2 the resistivity and temperature of ultrapure water for CEDI QC monitoring. Easy integration The recently released Siemens VNX E and EX modules operate at very high recovery to optimize water savings. With % recovery and no chemical regenerants, these highly efficient modules help Siemens lead the way to green energy efficiency and costs savings. The company's current platform of thick cell modules from low flow MX to high flow VNX are all tested using Mettler-Toledo Thornton monitors. Eight additional QC test stations were added in 2004 using Thornton 200CR transmitters and today the new Thornton M300 transmitter products are used for temperature and resistivity monitoring. According to Rahoul Bhagat, Quality Assurance Manager at Siemens Water Technologies Ionpure Products, We have never had to replace or change a Thornton monitor on our QC test stands. The meters are very reliable. Other than an annual calibration, they never require any additional maintenance. Patrick Buzzell, CEDI Product Manager describes the Siemens VNX E and EX Modules as simple enough to set and forget. Buzzell continues, After correctly setting the electrical current based on the feed water, the E and EX will consistently produce high purity water. Similarly, Thornton products from the 770MAX to the M300 have provided consistent long term performance for us. Simplifying the integration of our components for our OEMs is an important consideration for Siemens Ionpure products and one that is shared by Thornton. Find our how your pure water QC can benefit from Thornton instrumentation: Ionpure is a trademark of Siemens its subsidiaries or affiliates. QC test station at Ionpure Products showing Thornton transmitters Publisher / Production Mettler-Toledo AG Process Analytics Im Hackacker 15 CH-8902 Urdorf Switzerland Illustrations Mettler-Toledo AG Siemens Water Technologies MKS Instruments Inc. Babar760 Dreamstime.com Subject to technical changes. Mettler-Toledo AG 07/10 Printed in Switzerland. 2 METTLER TOLEDO Microelectronic News 2

3 UniCond Resistivity Sensors Breakthrough Resistivity Sensors High Performance over Wide Range New cutting edge technology allows accurate conductivity / resistivity measurement over a vastly wider range. The same robust titanium sensor can now operate in all stages of water treatment, without compromising reliability or accuracy. Previous limitations With conventional conductivity measurement, two or more sensors with different cell constants are sometimes needed to cover the range from raw, reclaimed or recycled waters through the purification stages to pure water. This sometimes causes mix-ups in sensor types and locations and requires a greater variety and quantity of spare parts. Also with conventional sensors, the user must remember to manually enter the precise cell constant and temperature calibration data for each individual sensor into the transmitter s memory to achieve rated accuracy. In addition, installations typically locate the sensor directly in-line in the system at a considerable distance from the transmitter and control panel. Over the years, Thornton has optimized the wiring and signal handling to minimize cable capacitance and resistance effects so that accurate measurements are provided. Nevertheless, these effects do cause some measurement limitations. Unified, universal solution Based on Thornton s technology-leading experience with conductivity / resistivity and recognizing the opportunity to make significant improvements, Thornton engineers developed a miniaturized measuring circuit that could be embedded in the top of the sensor and send a robust digital signal to the transmitter. This unified design reduced the effective wiring distance between the sensor and the measuring circuit to a couple of centimeters! Without the effects of long cable capacitance and resistance, more sophisticated measuring techniques became possible. Because leadwire effects became negligible, electrochemical factors affecting the measurement could be dealt with more directly to improve rangeability. Measurement from ultrapure water to brackish water up to 50,000 µs / cm can now be made with a single UniCond sensor with excellent accuracy. This remarkable rangeability provides a number of advantages. Covering the entire range of most water treatment systems, the UniCond sensor becomes universal and simplifies specification, documentation, installation, wiring, operation and ordering of spare parts now actually, one spare part. UniCond sensors utilize Intelligent Sensor Management (ISM) technology, which maintains precise factory calibration data, as well as sensor identification, serial number, etc. in an internal memory. This enables simple Plug and Measure startup, eliminating manual data entry and any chance of operator error. Superior accuracy and reliability The UniCond sensor is also more accurate because it is calibrated as a system, which includes the cell constant, the temperature sensor and the measuring circuits. With all of these components integrated for calibration, individual errors are no longer cumulative. There is no added error by combining separate sensors and transmitters, each with their own limits of error. The advantages with UniCond conductivity/resistivity sensors are significant: higher accuracy, wider rangeability for greater standardization, and easier, more foolproof startup. For more information, go to: UniCond resistivity sensor METTLER TOLEDO Microelectronic News 2 3

4 Eliminating TOC in UPW LIQUOZON Ultra ozonation system with Thornton 770MAX instrument Ozonation Destroys Organics in Ultrapure Water Systems Semiconductor industry guidelines require TOC levels of less than 1 ppb for UPW systems. Ozonation systems such as the LIQUOZON Ultra from MKS use the Thornton 770MAX to help achieve this specification in a controllable and reliable equipment configuration. UPW in microelectronics production The microelectronics industry requires ultrapure water (UPW) for its manufacturing processes to assure high yields. Bacterial contamination is a critical problem for UPW production and maintenance, and it is aggravated by high total organic carbon (TOC) levels in the water. The International Technology Roadmap for Semiconductors (ITRS) guidelines therefore call for < 1 ppb TOC in UPW systems. Ozone is the most effective means of destroying bacteria and reducing TOC in process water and it has the advantage of maintaining product quality while providing significant water and energy savings. Equally important, ozone decays to oxygen and does not leave any residue; thus, it is ideally suited for microelectronics process water treatment. Effective ozonation US based MKS Instruments Inc., a supplier of technologies that enable advanced processes and improve productivity, offers a unique plug & play ozone system. The LIQUOZON Ultra packages all of the necessary components for ozone injection onto one skid, with material suitability, accurate dosage measurement and safety all in place. This on-demand dissolved ozone system is equipped with a Mettler-Toledo Thornton 770MAX dissolved O 3 measurement system strategically deployed for safety and control. Feedback control loops use these measurements to maintain ozone concentrations in the DIO 3 loop. Several locations in the loop need to be monitored for ozone concentrations to ensure proper system operations. These include the return line from the loop to ensure proper dosage control and downstream of the in-line UV ozone destruction unit to confirm that no ozone is present in the product water. Benefits Ozonation is an effective method for bacteria and TOC reduction in stored and distributed UPW systems, as it removes both the micro-organisms and the nutrients for further bacterial growth. Modern ozone systems such as LIQUOZON Ultra, flexibly and reliably produce variable concentrations and flows of ozonated water that are suitable for use in a variety of UPW system configurations. The Thornton 770MAX multi-parameter transmitter supports multiple points of ozone measurement plus conductivity and temperature to support this convenient package. Find out more at: LIQUOZON is a registered trademark of MKS Instruments, Inc. 4 METTLER TOLEDO Microelectronic News 2

5 Cost-efficient DO Measurement Controlling Dissolved Oxygen Essential for Semiconductor Quality A large Asian semiconductor foundry requires very low dissolved oxygen (DO) in their ultrapure water system. Reliable and accurate measurements using Mettler-Toledo Thornton instrumentation help meet these requirements at substantially lower cost. Major semiconductor foundry To ensure reliable performance of their technology-leading manufacturing operations, one of Asia s largest semiconductor producers takes great care to minimize DO in each of their four ultrapure water system polishing loops. Concentrations of cleaning / rinsing water are maintained at less than 10 ppb and usually below 5 ppb to minimize oxidation of ultra shallow junctions and other critical areas. Higher levels of DO could result in failures and low yields at great financial cost. Instrumentation choices Dissolved oxygen instrumentation has been a high priority at this facility. For this reason, the foundry s original instrument choice was a very expensive system with a reputation for accurate measurement. However, the system also required extensive, time-consuming maintenance procedures and costly replacement parts. After accepting these expenses for some time the foundry decided to explore alternatives. to stabilize after an air calibration. The performance was so good that they decided to obtain another unit, packaged by Mettler-Toledo Thornton Service as a portable verification system to use as a trouble-shooting tool for various points in their UPW systems. Accuracy and response advantages When the Thornton High Performance sensor measurements were compared with the more expensive instrumentation, they produced very similar values, with comparable response after both systems had been independently air calibrated. Evaluation personnel found that the actual time to perform the air calibration as well as the recovery time afterwards was much faster with the Thornton system. Long-term savings The Thornton sensor is operated with only ml / min of sample flow which saves a substantial amount of costly ultrapure water since measurements are made continuously, 24 hours a day. The savings on ultrapure water, service parts, calibration and maintenance time, plus the lower initial price of Thornton sensors is being used to justify replacement of additional measurements in the plant. They installed a Thornton High Performance Dissolved Oxygen sensor for comparison. The foundry personnel were impressed by the Thornton sensor performance, especially the speed of response, as well as the greatly simplified maintenance. After an air calibration the Thornton sensor stabilized in the low ppb range in less than 1 hour whereas their previous equipment required 2 to 6 hours Custom portable dissolved oxygen monitoring package using the Thornton M300 transmitter and High Performance DO sensor METTLER TOLEDO Microelectronic News 2 5

6 In addition, Thornton M300 transmitters offer multi-channel, multi-parameter capabilities which enable DO measurement to be paired with conductivity or resistivity plus temperature measurements, all on the same transmitter. Having a common platform for multiple parameters saves substantially on documentation, training, maintenance and spare parts. If you want to benefit from Thornton instrumentation at your facility, go to: Thornton High Performance DO sensor M300 transmitter Improved Resistivity Accuracy in UPW Systems Mettler-Toledo Thornton has devised new and innovative methods for field calibration of resistivity transmitters and sensors to achieve higher levels of accuracy in ultrapure water systems. Reference Standards Ever-increasing demands The water purification industry consistently demands higher accuracy resistivity measurements. Mettler-Toledo Thornton has responded by expanding measuring ranges with improved technology and by reevaluating existing calibration processes. Four factors contribute to overall system accuracy: 1. The transmitter resistance circuit 2. The transmitter temperature circuit 3. The resistivity sensor cell constant 4. The resistivity sensor Resistance Temperature Device (RTD) or temperature sensor Transmitter calibration Transmitter resistance and temperature circuits are calibrated by connecting precise resistance values to the sensor inputs and adjusting the transmitter s gain computation until the input value equals the displayed value. This can be performed using resistors traceable to national standards or with automated fixtures whose internal resistors are traceable to national standards. Mettler-Toledo Thornton offers instrument-specific calibrators that plug into sensor inputs and contain traceable resistances needed to calibrate all resistivity and temperature ranges of their instruments. Procedures for doing so are included with the calibrators. Sensor calibration Sensor calibration is more challenging because of the impracticality of removing a sensor from a process water system and the desire to calibrate at or near the sensor s operating point. The resistivity sensor calibration process produces two calibration factors, the resistivity multiplier (also know as the cell constant) and the temperature multiplier. These factors are determined by placing the sensor in known resistivity samples at a controlled and known temperature. The factors are generally computed in a laboratory environment under controlled conditions. Field calibrations pose significant challenges because in many 6 METTLER TOLEDO Microelectronic News 2

7 Best Practice Simplify your process with multi-parameter solutions The Mettler-Toledo Thornton 770MAX allows you to measure up to four analytical water parameters at once using one transmitter, thus simplifying your entire process. Find out more at: applications the removal of a sensor from an industrial process for calibration is impractical. The uncontrolled environment in which the sensor is located makes it difficult to calibrate with known standard solutions. Using a reference standard The Mettler-Toledo Thornton 1885 portable calibration system utilizes a reference resistivity sensor that has been calibrated in standard solutions with traceability to ASTM International and its temperature to the National Institute of Standards and Technology (NIST). This reference sensor, mounted in a sealed flow chamber and connected to a Thornton 770MAX instrument, measures a side-stream sample delivered through a very short length of user-supplied tubing. By utilizing the Mettler-Toledo Thornton 1885 portable calibration system, a calibration technician can connect the reference resistivity standard sensor to a sample port near the sensor and calibrate the in-line sensor with accuracy and traceability to national standards. In water systems with stable water temperature and with thoroughly insulated tubing and flow housing, a 1-point calibration may be executed on a sensor s temperature measurement to further improve the system accuracy. Many ultrapure water systems have a variety of resistivity sensors that have been purchased at different times and calibrated against different standards. Even small variations in standards can contribute to significant inaccuracies in a large water system. By using a single portable standard to calibrate all the resistivity sensors in the water system, the entire water system accuracy can be greatly improved and accuracy errors, due to variation in reference standards, eradicated. As the demand for ultrapure process water quality improvement increases, industry expectations will grow for more accurate resistivity measurements. Using existing technologies and uniquely innovative calibration methods, Mettler-Toledo Thornton is able to offer more precise and accurate resistivity measurement to meet industry demands. Find out more at: Thornton 1885 portable calibration system METTLER TOLEDO Microelectronic News 2 7

8 Comprehensive Website The Information you Want is at The new-look METTLER TOLEDO Process Analytics website contains a vast amount of up-to-date information on all our products and services. Content is localized for your country and tailored to suit your selections. The home page has been designed to get you quickly to the products and news you are interested in Simple layout allows you to quickly find the information and features you are looking for. j Learn about our most recent product developments j Register for free webinars j Request further information on products and services j Obtain a quote quickly and easily j Download our latest white papers j Read case studies relevant to your industry j Access buffer and electrolyte solution certificates j and more... 8 METTLER TOLEDO Microelectronic News 2

9 Product pages provide a product overview and quick access to all important details and documentation Application pages help guide you to the products that are right for your processes j Read the latest product news j Access our newsletter archive j Find out when our next trade show or exhibition is in your area j Register for free webinars presented by our industry experts j Download our white papers METTLER TOLEDO Microelectronic News 2 9

10 The THORNTON Solution One Transmitter for Multi-Parameters for TOC, ph, Conductivity, DO THORNTON solution Mettler-Toledo Thornton is the market leader in critical ultrapure and pure water analytics. Our 770MAX instrument is a multiparameter meter with a broad range of measurement sensor options. Wide range of instruments for your processes The in-line 5000TOC rapidly detects organic contamination in real time. As well as TOC, THORNTON produces sensors for monitoring ph / ORP, DO 2 / DO 3, conductivity, flow and pressure. j 770MAX multi-parameter transmitter Flow Smart j 5000TOC sensor for continuous Total Organic Carbon measurements j ph for ultrapure water applications j 2-electrode and 4-electrode conductivity sensors ph / ORP DO 2 / DO 3 10 METTLER TOLEDO Microelectronic News 2

11 THORNTON benefits j All-in-one supplier with sensors for all your pure water analytics needs j Multi-parameter transmitter capabilities saves panel space and lowers costs per parameter Transmitter 770MAX Smart Pressure / Tank level j 5000TOC allows a real-time TOC measurement, in-line, all the time j No gases or reagents to handle, store or replace for TOC sensor; absence of moving parts minimizes routine maintenance Smart Smart Conductivity j Smart Sensor technology offers Plug and Measure communication from sensor to transmitter j Sterilizable sensors designed for exceptionally long lifetime TOC METTLER TOLEDO Microelectronic News 2 11

12 Get in-line with METTLER TOLEDO Save Time Programming Your Transmitters Thornton s configuration tool is included with each M300 transmitter to enhance the value of simple and consistent programming. This tool provides a means to upload or download transmitter configuration and can store configuration files for later use. The transmitter configuration tool, with its bi-directional capability, greatly reduces the time required to program transmitters and assures consistency in programming. The M300 transmitter measures conductivity, resistivity, ph, ORP, dissolved oxygen and/or dissolved ozone. With four display lines and four analog outputs, the M300 can provide full capability on both analytical measurements and temperatures. Mettler-Toledo AG Process Analytics Im Hackacker 15 CH-8902 Urdorf Switzerland Visit for more information