How Customized Equipment Has Improved the Silicon Wafer Cleaning Process

Different customized systems or custom components may improve silicon wafer cleaning processes because customers have special requirements or because the process characteristics are unusual. Suppliers taking on such projects must have extensive in-house experience and expertise together with a board line of silicon wafer cleaning equipment to provide custom solutions. When customization is required, effective solutions can improve throughput, lower costs, and result in higher output quality and yield. Modutek has both the experience and in-house expertise required to offer such customized equipment.

Customized Software

Modutek’s SolidWorks Simulation Professional and SolidWorks Flow Simulation software allows customers to calculate chemical doses accurately as well as track chemical usage. Such calculations are especially important for custom installations because the inputs and the values obtained may be non-standard. Modutek develops and writes all its own software so the company can make adjustments and implement software customization whenever it’s required by a customer. This means that customers can rely on software that corresponds to their customized systems rather than trying to operate a custom system with standard software. Modutek’s software can tailored to precisely control and monitor even the most customized installations.

Custom-Fit Equipment

A lot of the equipment that goes into a silicon wafer cleaning installation has to fit into an existing space or fit other limiting installation parameters. Such custom-fit equipment may include:

  • Megasonic systems
  • Teflon tanks
  • Quartz baths
  • or other custom equipment

Modutek can build custom versions of these components to fit any existing or new wet process system to optimize the silicon wafer cleaning process. Megasonic cleaning systems can be customized for frequency and power while tanks can be sized according to custom requirements and can be fitted with heaters or re-circulating pumps as required. In each case, Modutek can analyze the silicon wafer cleaning application and recommend the most appropriate solution.

Custom Wet Bench Station Design

When preparing a custom wet bench station design, Modutek first looks at the process specifications. The software, chemical delivery systems, baths and wafer handling must all fit together to satisfy the process requirements. Sometimes customized components can be used in a standard configuration but at other times specially designed components may be arranged in a custom system.

This approach provides end-user flexibility while respecting customer specifications and ensuring that the equipment performs as expected. All systems are designed and built at Modutek’s company facilities based on their own in-house expertise and experience.

Customized Wet Process Systems

Wet process systems can be customized at the component or system level, but they can also feature customized levels of automation. Standard systems are manual, semi-automatic or fully automatic but special solutions are always possible. Customers may want a manual system but also want certain process sub-steps to run automatically. A customer may want the handling of hazardous chemicals to be fully automated for safety reasons but want the rest of the process to be manual. On the other hand, a fully automatic system may have a requirement for operator intervention at a specific point. Because Modutek designs these systems in-house, such customization is seamless and problem-free.

Customized wet process systems can find application in many research and industrial fields. A customized system is often needed for prototype development and testing since the prototype can have unusual or unique features. Cutting-edge research and development in industry or at universities may also require the special characteristics available from customized systems. Even full production manufacturing facilities may need customization if they want to try special cost-cutting or quality-enhancing production methods. In each case Modutek can analyze the requirements and propose solutions.

With over 35 years of experience in wet process technology, Modutek has pioneered customization as a tool for improving silicon wafer cleaning processes and continues to develop unique customized solutions for its customers. If you need a customized solution for your application contact Modutek for a free consultation or quote.

How Silicon Wet Etching Processes Are Improved with Specialized Equipment

how-silicon-wet-etching-processes-are-improved-with-specialized-equipmentWhile Modutek’s wet bench equipment supports all common wet etching processes, the continuous development of new wet bench technologies allows the company to offer specialized equipment that can improve performance for specific applications. Key factors for high output quality, fast processing, high yields and reliable outcomes are cleanliness, repeatability, tight control and precise dosages. Modutek’s standard line of silicon wet etching equipment already scores highly on these factors but the company’s specialized equipment can further improve performance for certain processes.

Buffered Oxide Etch (BOE)

The BOE process requires tight and precise temperature control while filtering lowers the particulate count and reduced acid consumption results in lower costs. Modutek’s F-series sub-ambient circulation bath is specially designed for BOE applications and addresses these factors. The temperature controller is accurate to less than plus/minus one degree centigrade in a range from 10 to 60 degrees centigrade with sub-ambient capability. The circulating bath includes 10.0 to 0.2 micron filtration and is designed for low acid consumption. Using a wet bench system specialized for the BOE process can reduce costs and defects in products while providing safe and reliable operation.

Piranha Etching

The sulfuric acid/hydrogen peroxide mixture of the Piranha solution is extremely corrosive, and the mixture is exothermic when first prepared. The Modutek QFa Series of Quartz High Temperature Recirculating Baths are ideal for withstanding the high temperatures, first of the initial heating after mixing and then during the process that is heated to preserve mixture reactivity. The baths have heaters that can raise the temperature of the mixture by two degrees Centigrade per minute and the temperature controller can maintain the temperature at plus/minus one degree centigrade over a range of 30 to 180 degrees centigrade. These Modutek quartz baths are characterized by the high degree of safety, reliable operation and low cost of ownership.

Potassium Hydroxide (KOH) Etching

Modutek Teflon tanks are ideal for use in KOH etching because they can be custom fitted to any wet bench configuration and come in three models to satisfy common heating and recirculating requirements. The TFa and TI series of Teflon tanks are temperature controlled to an accuracy of plus/minus 0.5 degrees centigrade over a range of 30 to 100 degrees centigrade. The TFa series are overflow re-circulating models while the TI series are static. The TT series are static ambient temperature models. All Teflon tanks are made from PFA Teflon with special welding techniques to minimize the presence of undesirable by-products in the process and to reduce contamination. Modutek’s Teflon tanks improve KOH process control, increasing reliability and reproducibility of process conditions.

Silicon Nitride Etching

Etching silicon nitride with a phosphoric acid deionized water mixture is challenging because the concentration changes as the deionized water evaporates and because adding water to the process can cause an explosion. Modutek’s silicon nitride wet etching bath is specially designed to address these issues and provide reliable and safe process control. The mixture is kept at the boiling point, which changes as the concentration increases. Depending on the temperature of the mixture, small amounts of deionized water are added to the boiling mixture to maintain the concentration at the required level. Using the boiling point temperature as an indication of the concentration and allowing the boiling mixture to immediately distribute small amounts of water lets Modutek control the process while maintaining safe operation.

With its extensive experience in silicon wet etching process technology, Modutek can deliver specialized equipment suited to a particular process and help customers select the right equipment for their applications. With equipment specially designed for the process used, customers obtain superior results while often saving money as well. Contact Modutek for a free consultation or quote on using the right silicon wet etching equipment for your application.