Monthly Archives: September 2022

Chemical Handling for Wet Processing Equipment

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Chemical Handling for Wet Processing EquipmentBecause wet processing of silicon wafers uses different types of chemicals, semiconductor manufacturing facilities need chemical handling equipment to store, deliver and dispose of the chemicals. A complete chemical handling system takes care of all aspects of chemical use and ensures chemicals are delivered to the process when and where needed.

For corrosive, toxic, or flammable chemicals, safe handling is critical. Most of the chemicals used in wet processing can’t be released into the environment without additional treatment. Neutralizing dangerous chemicals on site or storing them in safe containers until they can be transported to a treatment facility must be documented to comply with local regulations.

Since chemicals are often dangerous to the employees operating wet processing systems, the chemical handling equipment has to be designed to minimize spills and reduce employee exposure to chemicals and their fumes. A comprehensive chemical handling system can improve workplace safety, reduce spills and waste, and make chemical processes more efficient.

Chemical Delivery Systems Provides Your Process the Chemicals It Needs

Chemical delivery systems store the chemicals safely and then deliver the right quantities, mixtures, and concentrations directly to the production line. The amount of chemicals delivered has to be precise and repeatable. Successful wet processing often depends on the right mixture or concentration because etching, stripping, and cleaning can vary with the amount of chemicals in the bath. When processing batches, the amounts delivered must be precisely the same for each batch. With continuous processing, the chemicals delivered can’t vary over time.

Modutek has a complete range of chemical delivery equipment, from high volume systems for large continuous production lines to small batch operations. Chemicals can be stored remotely in large totes with a load cell interface or in 55-gallon drums near the wet process station. Modutek’s SolidWorks Simulation Professional and SolidWorks Flow Simulation applications can calculate the exact quantities of chemicals required, and the chemical delivery systems provide precisely the calculated amounts. These systems ensure that chemical handling and process repeatability are excellent.

Modutek’s Collection Systems Remove Used Chemicals from Processing Stations

Once a wet process such as cleaning, etching, or stripping is complete, the used chemicals must be removed from the process stations and collected. Chemicals can be stored in safe containers and sent to a company specializing in neutralizing and disposing of hazardous chemicals, or they may be neutralized on-site.

To collect the chemicals from processing stations, chemical lift stations can pump the chemical waste from the process tank to a storage container. Chemical carts, also called pump carts or collection carts, can be moved near the process tanks to empty smaller amounts of chemicals. Storage can range from small carboys to large collection tanks. For small volumes, waste chemicals can be pumped directly into a five-gallon DOT-approved carboy for subsequent shipping to an off-site neutralization facility.

Acid Neutralization Systems Ensure Compliance with Environmental Standards

Many wet process semiconductor manufacturing steps use strong acids in their process baths. The used acids must be disposed of safely without risks to employees, the general public, or the environment. Local regulations specify how acid waste must be treated to ensure that disposal meets these requirements.

As regulatory compliance becomes more complex, the costs of disposing of chemical waste off-site are increasing. Modutek can provide self-contained acid neutralization systems that are inexpensive to operate. These systems add neutralizing chemicals to the acid waste and track chemical use, waste pH, and discharge quantities. The systems can generate documentation for regulatory compliance and safely dispose of the neutralized waste.

Modutek Offers In-House Expertise for Selecting Chemical Handling Equipment

Modutek can help customers choose the right chemical handling equipment for their facility. In-house experts at Modutek can recommend equipment from a full line of chemical handling systems. Modutek can customize equipment for special applications and ensure that the systems meet customer needs. Contact Modutek today for t a free consultation to discuss your chemical handling needs.

Easy to Install Wet Processing Equipment for R & D

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Easy to Install Wet Processing Equipment for R&DWhen research labs need to produce semiconductor prototypes or small quantities for testing, it’s often too expensive to place an order with a wet process production line supplier or to purchase complete wet process stations. Modutek has developed innovative tabletop models that are less expensive than full-sized wet process manual stations and take up much less room. They support the most common wet process cleaning, etching, and stripping steps, and Modutek can customize the units for special applications. The new Modutek tabletop units are easy to install and ideal for small-quantity R&D applications.

Modutek’s Table Top Units Are Feature-Rich and Versatile

Modutek has designed its new tabletop wet processing units to satisfy various R&D needs. The Teflon tank models support acid process steps such as KOH etch and buffered oxide etch (BOE), while stainless steel models support solvent process steps such as solvent resist strip. Tanks are available for ambient temperature or temperature-controlled operation, and they can be static or re-circulating with a filter and an all-Teflon fluid path. The temperature-controlled models have precise controls with rapid and even heating of the bath. The tanks come with temperature and level alarms and a drain interlock.

The compact and simple design of the tanks makes them easy to use, and operators can quickly get excellent results. The standard units that support the most common wet process steps allow the production of many different types of semiconductors. Modutek can customize its tabletop units to support additional silicon wet etching processes as required.

Modutek’s Table Top Units Support KOH Etch

KOH etching is popular because it delivers precise results using a relatively safe process. As such, it is well-suited for tabletop R&D applications. The etch rate depends on potassium hydroxide (KOH) concentration and temperature in the process solution. The etch direction can also be influenced by the silicon lattice’s orientation and the silicon’s boron doping. Different etch control strategies allow operators to etch various shapes into the silicon wafer.

The concentration of KOH may vary from 10 percent to 50 percent, but it is usually at around 30 percent. The orientation of the silicon crystal lattice means that the etch rate is faster in one direction, and Boron doping stops the etch progress in the direction in which the boron is found. These control factors are determined by the design of the etch shapes before the start of the process. Once etching has begun, the temperature allows operators to further control the etch rate and influence the shapes of the etched cavities. Because KOH etches can be controlled in different ways, it is the etch process most commonly used in Modutek’s tabletop units.

Using Modutek’s Table Top Units for Sub-Ambient BOE Etch and Solvent Applications

BOE etching is used to etch patterns in silicon dioxide films or to remove such films from the silicon wafer surfaces. The etching solution contains hydrofluoric acid, and a low temperature reduces consumption. The units that support BOE are the circulating, filtered models that are also fitted with a heater/chiller. Sub-ambient operation down to 10 degrees centigrade is possible.

Solvents used in semiconductor manufacturing steps, such as solvent resist strip, require stainless steel tanks and special safety features. Solvents, such as acetone, are flammable, and Modutek’s tabletop units include measures to prevent fire and explosions. Modutek can customize solvent and acid tabletop units to support other wet-process applications and add special features as needed.

Modutek Can Provide Custom Units for R&D Applications

Modutek has extensive in-house experience designing and building silicon wet etching equipment. If you need equipment to support R&D functions, tabletop units are an excellent option that can be customized to support many wet-process applications. Contact Modutek for a free consultation to discuss your application requirements.