Tips on Selecting an Acid Neutralization System for your Application

Tips on Selecting an Acid Neutralization System for your ApplicationAcid neutralization systems are essential for various industrial processes such as semiconductor fabrication and research facilities that produce acidic effluents. These cannot legally be discharged directly into public sewer systems; instead, they need to first be processed in legally prescribed ways. Altering the pH of acidic waste by-products to legally acceptable pH ranges of between 6 and 9 can be a major challenge, however.

As process engineer or semiconductor facility manager, what do you look for in an acid neutralization system? The best solution is a system that is easy to use, has a low operating cost and complies with all laws and regulations. Managers tend to see waste treatment as an operation that is difficult to administer and control costs in. The use of an effective system that provides automation would be the best option.

Automation frees up resources and lowers costs for businesses. When equipment is properly maintained to manufacturer-recommended specifications, a business can easily manage the process to meet specific criteria.

Acid neutralization systems treat acidic effluents using either continuous-flow processing or batch processing.

Considering a Continuous-flow Neutralization System

Continuous flow neutralization — where a stream of influent is treated while in flow through a pipeline system, prior to discharge — tends to work well in applications where there is a high rate discharge of mild acid or alkali. Continuous flow systems tend to be practical as long as the pH of influents remain stable from one moment to another.

Most systems offer a two-stage handling process; these can be effective for processes that produce moderately acidic effluent. Three-stage processes work well for processes that produce especially polluted effluents.

An automated, continuous-flow neutralization system is designed to provide acid neutralization within the confines of a compact unit, and can process streams as high as 500 gallons per minute.

With microcomputer-controlled monitoring at every stage, there is a high level of reliability to ensure compliance.

Considering a Batch Neutralization System

Acid neutralization systems that handle influent waste acid in batches can be effective in certain applications. Unlike continuous flow systems, batch systems are able to effectively deal with complex, highly acidic influents. Batch systems are suitable in the treatment of processes that cannot be relied upon to produce effluents of stable character. When acidic content tends to change, batches of waste need to be collected and treated separately. Batch neutralization systems also excel in the treatment of influents that are complex in nature — ones that contain heavy metal and fluorides.

These systems come with excellent automation benefits that include:

  • The automation of chlorination and pH adjustment for removal of bacteria.
  • The programming of operational sequences where different reagents and polymer flocculants are fed in.

The Benefits of Choosing an Automated Solution

With an automated acid neutralization system in place, manufacturers are able to get by with a minimal amount oversight to this side of operations. Fully automated from end to end, these systems offer intelligent, sensor-based checks at every point to alert staff of any need for attention, should it arise. Operators can be assured that problems will not go unnoticed.

Modutek Can Help You Choose the Right System for Your Requirements

Modutek, a leading provider of equipment solutions for semiconductor manufacturers, offers a full range of neutralization technologies with different configurations. These are highly cost-effective systems both to install and operate. Modutek can assist process engineers and managers at manufacturing facilities to select the right equipment to meet their specific requirements.

How Teflon Tanks Are Used in Wet Processing Applications

How Teflon Tanks Are Used in Wet Processing ApplicationsModutek’s Teflon tanks are custom designed for use in new and existing wet processing stations. Their modular configuration allows easy integration in customer clean room facilities. Advanced PFA Teflon welding techniques reduce impurities and unwanted by-products in the process, and Modutek can supply heated models for use in processes that require temperature control. Standard carrier sizes are available for single or double capacity, and Modutek can design and build custom tanks for specific customer requirements. Additional options and features make Modutek’s Teflon tanks suitable for a variety of wet process applications.

Teflon Tank Configurations

Modutek offers three types of Teflon tanks:

  • The TT series are ambient temperature baths
  • The TI series are temperature controlled static baths
  • The TFa series are temperature controlled overflow recirculating baths

Modutek can work with customers to analyze their process requirements and recommend the best tank configuration. All tanks are manufactured from the highest quality material and come with first-class support from in house technicians at Modutek.

Temperature-Controlled Teflon Tanks

Modutek offers static and recirculating temperature-controlled Teflon tanks for KOH (potassium hydroxide) and TMAH (tetramethyl ammonium hydroxide) anisotropic etching of silicon. The heat sources can be in line and an immersion heater in the overflow weir. The tanks feature all-Teflon fluid paths and low level, high limit and high-temperature signaling. A drain interlock is standard.

The temperature control delivers fast heating of two to three degrees centigrade per minute within a range of 30 to 100 degrees centigrade. Process temperature control is accurate to within plus/minus 0.5 degrees and the tanks feature an optional Teflon refluxor with Teflon cooling coils. The fast and accurate temperature control system lets operators achieve excellent consistency and repeatability for temperature-sensitive processes such as TMAH and KOH etching.

Teflon Tank Features

Modutek designs their Teflon tanks for ease of use, convenient installation, quick repair and excellent compatibility with new or existing customer facilities. Specific features include:

  • 360-degree serration overflow
  • Manual cover with overlapping seal
  • Modular design
  • Minimal water loss
  • Consistent chemical concentration over time
  • One year warranty

The design of Modutek’s Teflon tanks results in fewer defects in output and a higher product quality overall.

Teflon Tank Options

Modutek tanks can be ordered with the following options:

  • A pneumatically operated automatic cover
  • Teflon gravity drain system
  • Aspirator valve system
  • An RS232 Interface
  • Remote operation timer switches
  • Temperature process controller/timer
  • Teflon refluxor with Teflon cooling coils
  • Magnetic stirrer for agitation
  • DI water or IPA spiking system

Benefits of the Modutek Teflon Tanks

Modutek’s design and configuration results in the following specific benefits:

  • Uniform heating throughout the bath
  • Accurate and rapid temperature control
  • Process etch variability wafer to wafer less than 2 percent
  • Modutek in house maintenance and repair support
  • Extensive customization to meet specific requirements

Based on the standard Teflon tank design, Modutek can use its design expertise to supply Teflon tanks of the highest quality, sized to customer specifications and with the features and options required for the customer’s application.

Modutek Support

With over 35 years experience in wet bench stations, Modutek can offer effective support for customer wet process applications. The company manufactures a full line of semiconductor fabrication equipment and can help customers analyze their needs. With its wet process expertise and its experienced technical personnel, Modutek can offer help with selecting the best possible wet bench equipment configuration. The company offers free consulting to ensure that customers select the right equipment. Whether it is Teflon tanks or a complete wet process semiconductor manufacturing line, Modutek can help determine what the requirements will be, suggest optimal solutions and deliver the appropriate equipment.