How Quick Dump Rinsers Improve Wet Processing Results

While effective and rapid rinsing with a low particle count remains a key benefit of quick dump rinsers, reduced water usage is also becoming more important. Special design measures can lower the amount of water required to rinse the silicon wafers while retaining fast and efficient operation with a low level of particle contamination.

Low water consumption is especially important in some regions such as the Western U.S., where a long-term drought makes water conservation mandatory. Even in other areas, a reduced use of the deionized water used in silicon wafer fabrication saves money and is environmentally responsible. Modutek has pioneered the design of quick dump rinsers that feature efficient use of deionized water, fast operation, and low particle entrapment.

Quick Dump Rinser Benefits that Incorporate Reduced Water Usage

Modutek’s quick dump rinsers feature a state-of-the-art design for efficient operation while minimizing rinse time, reducing the particle count, and keeping deionized water usage to a minimum. Modutek’s quick dump rinsers offer the following characteristics:

  • Efficient Rinsing. The units have dual spray manifolds and low misting nozzles for quick and complete rinsing away of chemical residues.
  • Nitrogen Bubbler. The bubbler generates nitrogen bubbles as the tank fills, removing additional contaminants and particles.
  • 360 Degree Overflow Weir. As the dislodged impurities rise to the surface, they are flushed away across the overflow weir and out of the tank.
  • Programmable Water Use. Modutek’s quick dump rinsers can be programmed to use less water.
  • Contoured Bottom. The rinser bottom is contoured around a wafer cassette, reducing the amount of water required.
  • Large Machined Trap Door. The machined trap door doesn’t need gaskets or seals that could trap particles, and the large size lets water drain rapidly.
  • Polypropylene Construction. High-quality smooth polypropylene construction ensures that the tank is not a source of contamination with new particles.
  • Automatic Dump and Refill. The rinsing controller can be set to automatically dump and refill every two hours, reducing bacterial growth and minimizing the possibility of contamination.
  • Optional Reclaim System. An optional reclaim system further reduces water consumption and lowers costs.
  • Variety of Standard Sizes. Modutek offers seven standard tank sizes for their quick dump rinsers, and can accommodate many special customer needs.

Modutek has designed the quick dump rinser to operate as a stand-alone unit or for integration into a silicon wet etching process line. The rinser can improve the overall performance of the line and lower costs while reducing the number of defective products.

Benefits of Using Modutek’s Quick Dump Rinser

Modutek’s design is based on extensive experience working with wet process equipment to address key customer concerns. Benefits include the following:

  • The reduced water consumption due to rapid rinsing and a water-conserving design lowers costs and reduces the environmental impact.
  • The machined trap door and laminar flow of rinsing water reduce the particle count and improve output quality.
  • The smooth polypropylene construction avoids additional contamination and reduces the percentage of rejects.
  • Quick rinsing allows increased throughput for the production line and reduces costs.

From its close working relationship with customers, Modutek can address the challenges manufacturers often have with meeting higher product densities, smaller silicon structures, and increasing regulation with using chemicals and water. Modutek continuously works to improve silicon wafer processing capabilities, while keeping in mind the overall costs of ownership and efficient wafer processing.

Modutek Provides Innovative Solutions to Meet Customer Needs

Modutek’s quick dump rinsers represent years of innovative design and development. These systems let semiconductor manufacturers and research facilities reduce water consumption while increasing output and reducing the number of product defects. Overall facility performance is improved through cost reduction and improved output quality. Contact Modutek for a free quote or consultation to discuss your specific processing requirements at 866-803-1533 or email [email protected].

How to Select an Acid Neutralization System to Reduce Chemical Disposal

When industrial processes such as semiconductor manufacturing use chemicals, the chemical waste needs to be treated before disposal. Chemical waste treatment can be handled on-site with an acid neutralization system or companies can use outside service providers to pick up the waste and properly dispose of it.

Modutek’s acid neutralization systems are designed for easy and flexible installation along with reliable operation and low chemical consumption. The systems make it easy for customers to avoid the costs of hiring disposal companies by treating chemical waste in-house. For many industrial processes, the chemical waste treated with an acid neutralization system is safe enough to drain into the local sewer system.

Continuous Flow Versus Batch Neutralization Systems

For most large industrial operations, a continuous flow acid neutralization system is the best solution. The waste chemicals from a process are produced continuously and they are automatically treated. A continuous flow of 5 to 100 gallons per minute (GPM) can be neutralized. Smaller industrial facilities often operate in batch mode where small quantities of used chemicals need to be disposed of. Modutek’s acid neutralization systems treat and neutralize chemicals using the continuous flow method.

Flexible Installation Means Modutek Systems Are Suited for Many Different Applications

To reduce chemical disposal via an outside service provider, an in-house neutralization system has to be flexible and easy to install. Cost-effective systems have to feature low chemical consumption for complete neutralization allowing disposal into a local sewer. Modutek’s acid neutralization systems satisfy these requirements and can save customers money by reducing chemical disposal costs.

Additional installation features for various service applications include the following:

  • Indoor or outdoor installation
  • Working volume up 4000 gallons
  • 110% Secondary containment tank for extra safety
  • Final discharge sample tank with pH probe and chart recorder for compliance purposes
  • Acidic or alkaline chemical waste treatment in two or three stages
  • Fully automatic operation with a touch screen monitor
  • Unitized construction with larger systems skid-mounted
  • Microprocessor-based pH controls with a comprehensive alarm system

Modutek’s acid neutralization systems are designed to fit into existing process lines with just a plumbing connection and electrical hookup. Once installed, the systems offer problem-free chemical waste neutralization and disposal.

Sensors, Meters, and Automation Help with Ease of Operation

Modutek acid neutralization systems are designed to work reliably in fully automated mode while sensing chemical waste composition and triggering alarms when key variables show abnormal values. Electronic chemical metering pumps supply the correct amounts of neutralizing chemicals while Signet pH probes and transmitters monitor the composition of the chemical waste. Signet paddle wheel flow sensors and signet 9900 flow meters/totalizers send their signals back to a PLC that controls alarms. The systems are designed to work independently while providing readouts for operators tracking the process. Chemical use, discharge pH, overall flow, and triggered alarms are recorded. Operators can make sure that discharged waste stays within the environmental regulatory framework and can use the recorded data to demonstrate compliance with proscribed values.

Modutek’s Expertise in Chemical Processing and Neutralization

By working closely with customers and industry partners, Modutek provides continuous innovative products to meet customer needs. Modutek has its own in-house expertise to evaluate specific applications and make recommendations. After identifying process requirements, Modutek can make suggestions and offer systems from its complete line of chemical handling equipment. For a free quote or consultation to discuss your chemical processing and neutralization requirements contact Modutek at 866-803-1533 or email [email protected].

How Optimum Particle Reduction is Achieved in a Wet Bench Process

When microscopic particles remain on the surface of silicon wafers during a wet bench process, the resulting semiconductor products may be of reduced quality or even defective. As semiconductor geometries and microscopic structures become smaller and are packed more densely on a silicon wafer, the presence of particles can influence the etch rate around the particle and compromise semiconductor fabrication. The smallest structures and conductor paths can be influenced by particles in the submicron size range and these particles are especially difficult to remove completely.

Modutek has developed innovative solutions that achieve particle reduction through reduced handling of wafers and excellent particle removal. The single chamber IPA Vapor Dryer and the use of megasonic cleaning deliver excellent results. The reduced particle count produces better yields and higher quality output. At the same time, Modutek’s solutions save money through the reduced use of chemicals.

The Single Chamber IPA Vapor Dryer Keeps the Particle Count Low

Modutek’s single chamber IPA Vapor Dryer incorporates rinsing and drying in a single system to save space, reduce costs, and minimize the handling of silicon wafers. The system initially rinses the wafers with de-ionized water and then introduces IPA vapor into the drying cabinet. The vapor comes from a one-gallon bottle that is located in the exhaust compartment for easy changing.

IPA vapor is introduced into the drying chamber from the top to ensure even distribution and reduce the amount of IPA required. When the IPA vapor condenses on the wafers, a surface tension gradient develops between the IPA and the remaining water. When water flows off the wafer surfaces it can remove the contaminating particles. The dry wafer surface doesn’t have any water marks and no particles are added.

One source of particles is the handling of wafers during transfers between stations. Reducing the number of transfers eliminates a source of particle contamination. Modutek’s Single Chamber IPA Vapor Dryer can handle an optional etching feature and drying in the same system. The wafers are rinsed and dried without transferring them to a new station. Since no additional particles are introduced during this process the particle count is kept to a minimum.

Megasonic Cleaning Effectively Removes Particles Without Toxic Chemicals

Megasonic cleaning relies on high-frequency sound waves in the cleaning solution to remove contaminating particles from wafer surfaces. Modutek has partnered with Kaijo Corporation, a world leader in megasonic cleaning systems to incorporate this technology in their wet bench equipment.

A megasonic generator feeds a high-frequency signal to a transducer immersed in the cleaning tank liquid. The transducer converts the signal into sound waves that travel throughout the tank. The sound waves generate microscopic cavitation bubbles that produce a scrubbing action to clean wafers. Particles on the surface of the wafer are dislodged and washed away.

The higher the megasonic frequency, the smaller the cavitation bubbles and the gentler the cleaning action. The microscopic structures etched into silicon wafers are very delicate and could be damaged with rough cleaning. Megasonic cleaning uses frequencies of 950 kHz and higher. The tiny bubbles of megasonic cleaning deliver gentle cleaning action without damaging fragile silicon structures.

Although megasonic cleaning works well with DI water or an SC1 process, adding a mild detergent or solvent can improve cleaning performance. Particles on silicon wafer surfaces often adhere to the surface and can be difficult to remove. Submicron particles may stay within a surface boundary layer, resisting removal. The microscopic bubbles can dislodge such particles, but the addition of solvents or detergents helps dissolve the bonds holding the particles to the surface and can improve particle removal.

Modutek Innovates to Help Meet Customer Challenges

Modutek works closely with customers to identify issues with wet process applications and continually works on developing new innovative solutions. The Single Chamber IPA Vapor Dryer and the megasonic cleaning process are innovations that help reduce particle counts while reducing chemical use and lowering costs. Modutek’s experience with wet processing equipment ensures customers will continually be able to improve their process performance results. Contact Modutek to schedule a free consultation to discuss your specific process requirements.

How Software Controls Achieve Best Results in Silicon Wafer Processing

Depending on the degree of automation, software controls can enhance wafer manufacturing facility performance and achieve improved results. Full automation lets operators take advantage of different operational modes to test new process steps and optimize process variables. The controls can then run the process with precise repeatability and often without operator intervention. The reduction in operator error, monitoring chemical concentration with dosing capability and the increased reliability can result in higher yields and reduced costs with more efficient silicon wafer processing.

Automation controls in wafer manufacturing equipment must be reliable and accurate enough to reproduce exact chemical doses and process times, but flexible enough to permit technicians to make changes when needed. An intuitive operator interface, transparent programming of process steps, and easy adaptation of variables to new requirements help achieve excellent results. Software controls that deliver reliable reproduction of existing processes along with flexible programming for responding to changing requirements can significantly improve facility output.

Software Must Combine Support for Current Operations and Meet Future Needs

Modutek’s software can set process parameters such as chemical dosage, wafer etching, and cleaning times as well as other process parameters. Touch screens with a Graphic User Interface (GUI) allow operators to see process status and intervene if necessary. The displayed process shows the information on the status of the processing equipment. In addition, all set points can be easily modified to reflect your requirements. The software Modutek provides combines operational reliability with the flexibility needed to adapt the programs to new situations or requirements.

Optional Equipment Interface Makes Sure Commands Are Executed Correctly

Modutek offers SECS/GEM protocol or Ethernet access for the data logging interface. This interface allows Modutek to make output changes and integrate new wafer manufacturing equipment while ensuring that software commands are executed properly and accurately. Operators can read displays of process characteristics on the GUI to ensure command execution takes place as expected. All these options are reviewed during the station design layout process to ensure it meets your process and budget requirements.

Peripheral Control Features Can Enhance Software Performance

Data logging can improve performance by providing operators with additional information that allows them to optimize operations. Data loggers can track indicators such as output, process temp, processing times, and all alarm features. All data can form the basis for an evaluation of facility performance and plans for targeted changes to reach clearly defined goals.

Modutek can integrate standard or custom peripheral control features as needed by customers for specific applications. Customers may require certain information to optimize their process or depend on output data for subsequent action. Modutek can analyze such requirements and add the necessary functionality, both in terms of sensors or additional equipment and to ensure the information is processed and presented in a useful format.

Designing and Building Advanced Software Controls to Improve Silicon Wafer Processing

As a leading wet bench manufacturer with extensive experience and expertise in designing and building equipment in-house, Modutek works with customers to ensure their software controls meet their needs. In addition to providing excellent customer support, Modutek can evaluate complex customer applications to propose the best possible solutions. Contact Modutek for a free consultation to discuss your manufacturing equipment needs.

How Advanced Ozone Cleaning Reduces Chemical and Solvent Usage

As environmental concerns mount and regulatory compliance becomes more difficult, companies that reduce the use of hazardous chemicals and solvents will have a competitive advantage. In addition to reducing costs, the use of fewer corrosive chemicals improves workplace safety and can lead to better semiconductor manufacturing facility performance. Modutek’s patented advanced ozone cleaning process saves money and reduces the contaminating particle count on wafer surfaces. Depending on process requirements, ozone cleaning can out-perform traditional wafer cleaning with harsh chemicals. Modutek’s ozone cleaning process is compact, fast, and safe.

Advanced Ozone Cleaning Converts Organic Impurities to Carbon Dioxide

Modutek has developed the Cold Strip sub ambient process that operates with deionized water and the Organostrip process that uses a mild acid at room temperature for photo resist strip. This also eliminates the use of NMP solvent base strippers. Both use ozone to clean organic contaminants from wafer surfaces and both leave harmless residues that allow for disposal without special neutralizing procedures.

The Cold Strip Advanced Ozone Cleaning Process operates at four to ten degrees centigrade and uses deionized water to strip silicon wafers of water-soluble inorganic impurities. After the wafers are rinsed with deionized water, ozone is introduced into the chamber. The ozone reacts with the remaining organic impurities and converts them to carbon dioxide. Particle contamination is reduced as well because the ozone reacts with organic particles. Wafers are more effectively cleaned with a reduced particle count.

In the Organostrip process, wafers are rinsed with a solution of a mild acid and ozone at room temperature. The acid has a high ozone solubility that lets the ozonated solution remove organic compounds from the wafer surfaces quickly and completely. The process is compatible with metals such as gold, copper, and aluminum, and the waste products of the Organostrip process are not hazardous.

Modutek uses its DryZone solvent gradient dryer for the Advanced Ozone Cleaning Process that the company developed to address customer concerns. Customers experienced high particle counts and issues with the use of hazardous chemicals, including their effect on the environment. The developed process successfully addresses these issues and delivers effective wafer cleaning.

Modutek’s Advanced Ozone Cleaning Process Provides Substantial Benefits

Modutek developed the Advanced Ozone Cleaning Process to address specific customer concerns, but the Cold Strip and Organostrip processes also improve wafer cleaning and facility operations. The benefits of using ozone cleaning include the following:

  • Reduced cost for process chemicals. The acids used in a traditional wafer cleaning process, such as sulfuric or hydrochloric acids, are expensive, and the cleaning processes such as Piranha clean use substantial volumes of chemicals. Ozone and the mild acids or solvents used in ozone clean are less expensive and the solutions last longer.
  • Reduced cost for chemical handling. The storage, delivery, and disposal of hazardous chemicals used for traditional wafer cleaning is expensive. The handling of ozone and the mild chemicals used for ozone cleaning requires no special measures.
  • Improved workplace safety. The chemical baths used for traditional wafer cleaning often operate at high temperatures and they can be dangerous. The ozone cleaning process chemicals are safe and the operation is done at sub ambient or at room temperature.
  • Higher throughput. Advanced ozone cleaning takes less time than traditional cleaning methods.
  • Improved yields. Ozone cleaning reduces particle counts and results in higher output quality with fewer product defects.

Modutek’s Continued Process Improvement Delivers Innovative Solutions for Customers

Modutek works closely with customers to identify new concerns and solve existing processing problems. Using extensive in-house experience and expertise in wet process technology allows Modutek to provide innovative solutions to meet customer needs. New wet process steps such as Advanced Ozone Cleaning can help customers improve semiconductor manufacturing facility performance and increase profitability.

How Better KOH Etching Results Are Achieved Using Teflon Tanks

While KOH etching is widely used, the process controls and the process tanks can play a major role in obtaining the desired results. Improved KOH etching means precise control of the etch rate and a low particle count. When the etch rate is exact and consistent, the etched shapes in the silicon wafer will be as specified and the final semiconductor product will function as expected. When particle counts are low, the number of defective products will go down and yield will increase. Combining Teflon tanks with high-precision control systems can deliver superior etching results while reducing waste and increasing output quality.

How KOH Etching Can Be Controlled and Improved

KOH etching uses a solution of potassium hydroxide to etch silicon wafers. The etch rate is influenced by the bath temperature, the concentration of potassium hydroxide, the orientation of the silicon crystal lattice, and possible doping of the silicon. Each of these factors helps determine how quickly etching proceeds in the horizontal and vertical directions.

The cubic crystal lattice of the silicon has different atom densities in different directions. The wafer can be oriented in such a way that etching proceeds more quickly in a given direction. Doping, or adding impurities to the silicon, can be used to stop the etching at a particular location in the wafer. While both these factors can influence the etch rate and the microscopic silicon structures, they are fixed before the etching process begins.

Because the etch rate partly depends on the KOH concentration, it is critical to add the right amount of KOH to water. An accurate chemical delivery system can help ensure that the etching tank contains the right solution concentration before the etching process starts.

The etch rate speeds up with an increasing temperature. This means that the tank and solution temperature must be raised quickly to the specified level and must be maintained precisely at the set point for the duration of the etching process. Accurate temperature control is important for improved etching performance.

Modutek’s Teflon Tanks and Controls Help Achieve Better Etching Results

Modutek provides temperature-controlled Teflon tanks and precise chemical delivery systems needed for excellent etching rate control for improved KOH etching results. These two process variables determine the KOH etch rate once the doped silicon wafer is placed in the process tank with the correct lattice orientation. After the etching process begins, the temperature becomes the critical factor in obtaining the desired etching results.

Modutek’s Teflon tanks are designed to minimize particle contamination and deliver fast heating with accurate temperature control. The tanks have an all-Teflon liquid path and are available in circulating or static models. The heater can be located in the overflow weir or inline. Even heating throughout the tanks ensures that the etching rate is the same everywhere.

To facilitate etch rate control, Modutek’s Teflon tanks heat up quickly at a rate of 2 to 3 degrees centigrade per minute. Once the set point is reached, the temperature controller maintains the temperature at plus or minus 0.5 degrees centigrade. The tanks can operate at 30 to 100 degrees centigrade and temperature and level limit settings can be applied. KOH etching proceeds quickly and reliably to produce the desired microscopic silicon structures.

Modutek Designs Teflon Tanks to Match Customer Requirements

Modutek’s in-house team works closely with customers to ensure that their wet process equipment meets their needs. While standard Teflon tanks are available, Modutek will design and build custom sizes with special features as required. Whether standard or custom designs, the high-quality materials, and precision controls ensure that KOH etch results satisfy even the most demanding requirements and that the Teflon tanks deliver the expected performance. For a free quote or consultation to discuss your specific process requirements contact us or call 866-803-1533.

Reasons to Use a Wet Bench Manufacturer with In-House Expertise

When dealing with third-party distributors who offer wet bench stations built by someone else, customers often pay more and get less. A wet bench manufacturer that designs and builds its own wet bench equipment in-house develops the expertise and capabilities needed to satisfy customer requirements. The manufacturer can respond directly to customer requests and design tailored or full custom solutions to meet specific requirements. With a wet bench manufacturer who has in-house expertise, customers can get exactly what they need.

Customizing Wet Bench Designs to Match Customer Needs Requires In-House Expertise

Semiconductor manufacturers and research labs often work with tight specifications that can’t be satisfied with standard wet bench stations. Customization requirements can range from space limitations to special robotics and software to control specific processing requirements. When manufacturers carry out their own design work, they are aware of the possibilities and limitations of specific semiconductor manufacturing processes. They can then easily advise customers what solutions are available and help choose the best one. Customers end up with optimized designs for equipment that works the way they want.

Building Custom Wet Bench Stations Requires Extensive In-House Manufacturing Experience

When wet bench manufacturers carry out their own design work, they know how to build what they design. Their designs are based on extensive in-house manufacturing experience gained over many years of building wet bench stations. They know what works and have been able to feed this experience back to their design engineers. With suppliers that carry out both design and manufacturing in-house, customers get wet bench equipment that is designed to their specifications and that is based on extensive manufacturing experience.

Wet Bench Manufacturers Can Provide Superior Customer Service and Support

With in-house design and manufacturing personnel, companies can provide knowledgeable customer support and after-sales service. When design, manufacturing, and process expertise resides in-house, service personnel know who to call if they run into problems. Support and service people will already be familiar with their own standard equipment and they have direct access to the design and manufacturing specialists that can guide them to find the best solutions for after-sales issues.

For wet bench technology, it’s especially important that the manufacturer also designs and writes the software that runs the process. Automation is becoming an increasingly important part of wet process equipment. Even if process steps are initiated manually, the software may be responsible for timing and dosages. For fully automatic stations, the software runs the whole process. Only the specialists who write the software can perform effective troubleshooting if there are unexpected operations or results. The wet bench manufacturer’s in-house expertise has to include the software.

Modutek Has Extensive Expertise Based on Long-Term Design and Manufacturing Experience

With over 40 years of experience in designing and building wet bench stations for industrial clients, Modutek is a leading wet bench manufacturer. Modutek works closely with customers to develop new technical solutions for current problems. In addition, Modutek actively leads technological innovation in fields such as wet bench process control, efficient chemical use, and reduction in particle contamination of silicon wafers. When customers identify new issues with semiconductor manufacturing, Modutek can often contribute to finding the best solutions.

Based on this long-term experience, Modutek personnel have developed extensive expertise in wet bench technology. The company designs its own equipment, including the development of its automation software. Wet bench stations are assembled and tested in-house at Modutek’s facility in San Jose which allows for easy customization. Modutek has a product line of standard equipment, including process tanks, chemical handling equipment, and complete wet process stations, the company can change dimensions, materials, robotics, process variables, and operator interfaces in accordance with customer requirements. In-house expertise is the key to these capabilities.

Why Ergonomics and Safety Are Important in Wet Bench Station Design

Because semiconductor manufacturing with wet bench technology uses dangerous chemicals in many of the process steps, ergonomic design helps keep employees safe. Toxic and corrosive chemicals such as hydrochloric acid are used to clean, etch and strip silicon wafers in wet process stations. Ergonomics helps ensure that operators don’t have to strain or overextend themselves when carrying out their work.

A safe working environment means that safety measures such as interlocks and alarms are in place, the risk of fire and explosions are minimized, and access to hazardous areas is restricted. Adequate employee training is a key factor in handling dangerous chemicals safely. Wet bench design has to take into account ergonomic factors when creating operator interfaces and safety measures to ensure the risks inherent in wet process operation are reduced to a minimum.

Ergonomics and Safety Can Increase Productivity and Employee Satisfaction

When the design of wet process stations makes it easy for operators to run each process step, increased comfort and safety allows them to focus on the work instead of worrying about possible mishaps. Safety has to be built into the stations, with prominent signaling of hazardous conditions such as spills, the use of explosion-proof measures such as low power electric signals, and the avoidance of flammable materials.

The Semiconductor Equipment and Materials International (SEMI) Safety Guidelines detail some of the measures that are required for wet benches, including guidelines for many aspects of semiconductor manufacturing. For example, SEMI S2 is a standard on safety labeling, safety interlocks, emergency shut down, electrical design, and ventilation. The SEMI S8 standard gives safety guidelines for the ergonomics of operation, maintenance, and service. Experienced semiconductor equipment manufacturers follow these guidelines because they realize that it makes sense to provide operators with a safe workplace and ergonomically designed equipment.

Modutek Incorporates Ergonomics and Safety Guidelines Into Their Wet Bench Station Design

Both Modutek’s standard lines of wet process equipment and customized versions are designed and built to the SEMI guidelines. Ergonomic design measures include features that make it easy for operators to carry out their work. Safety guidelines are followed so that the operation with the dangerous chemicals used in the process remains safe. For each wet process station, the ergonomic and safety requirements are either met or exceeded.

For example, ergonomic design has wafer loading trays brought to the front of the wet bench, making it easy for operators to load the trays. The operator interface is mounted on a swing arm, allowing operators to move it into different positions so they can see it while monitoring the process. The same thinking carries over to maintenance and service, where designs also respect ergonomic guidelines.

Modutek pays special attention to the safe design aspects of wet benches. Stations dealing with flammable substances are certified as hazardous locations to Class 1 Division 1 or Division 2. Safety interlocks are paired with process monitoring, leak detection, and alarms for dangerous conditions. Electrical controls are designed with low levels of power too weak for possible sparks to set off an explosion. Wiring satisfies NFPA 70 and 79 and there is an emergency off mushroom button.

Depending on the process, additional safety measures can include auto-lids to seal off the chemicals, gaseous automatic fire suppression systems, and access controls to ensure that only qualified operators can run the process. PVC safety shields, N2 head case purging and a deionized water hand spray may also be used.

Based on their extensive experience with the safe operation of wet benches, Modutek implements such ergonomic and safety measures while maintaining excellent operational reliability and superior yields. The complete line of Modutek wet process equipment is designed and built to the highest safety standards while delivering top-level performance for customers.

How Automated Wafer Fabrication Equipment Optimizes Process Control

Fully or semi-automated silicon wafer fabrication equipment can reduce errors and improve repeatability in wafer processing while at the same time increasing flexibility. Automatic controls let operators change process parameters if required for different processes or for process optimization.

Once a process runs in an optimized fashion, automated controls allow operators to make sure that the process continues to run the same way, either in a continuous mode or in batch processing. Automatic controls can ensure that an error-free process increases productivity, improves output quality, and reduces waste.

Automatic Controls Increase Operating Flexibility

Automatic controls use programmable software to specify how process steps operate and their sequence. The software determines the timing, chemical dosages, wafer transfers between stations, waste chemical neutralization, and chemical disposal. Once operators have programmed a process, they can carry out test runs and find where settings could be changed to improve the process results.

This means a process can be adapted to reflect changing requirements or can be changed so it produces better outcomes. At the same time, the process software in both semi-automated and fully automatic stations controls robotics that handles the wafers and reduce particle contamination. Automatic controls with the associated robotics can save money and produce semiconductor products with fewer defects and closer adherence to specifications.

Automated Operation with Robotics Contributes to Optimized Operations

Robotics handle and transfer the silicon wafers are a key part of the automated semiconductor manufacturing operations. For fully automated lines, multiple robots will hand the wafers down the process line. The robots have to operate to an extremely high level of precision to avoid damaging the delicate wafers and to place them precisely in the right locations. With the right robotics, properly programmed and fully automated, a semiconductor processing line can increase throughput and perform reliably to meet delivery times and volumes. Optimized process control combined with robotic speed and reliability can reduce costs and improve semiconductor fabrication facility performance.

For semi-automatic wafer fabrication equipment, the robotics generally handle less processing, however, Modutek has developed a new rotary rotation robot that can handle more process steps. The use of the rotary rotation robot can reduce the overall length and footprint size of a conventional station in a space-saving design. This allows manufacturing facilities and research labs with limited space to install semi-automatic fabrication lines using smaller stations with new robotics. As is the case for fully automated stations, semi-automatic controls and robotics can deliver increased speed, higher reliability, and improved facility performance.

Selecting the Right Automation Solution

Whether it is a fully automated process line or semi-automatic wafer processing equipment, automation can improve chemical handling and the cleaning and etching of silicon wafers. Software control ensures that chemical mixtures are correct, the timing of process steps is accurate and wafers are moved and transferred with a minimum of particle contamination. This allows wafer fabrication processes to be accurately completed with optimum efficiency and generates fewer defective components.

With more accurate process control, etch rates and yields can be higher and comprehensive tracking of variables delivers a complete picture of the process. Once the automated process has run for a large number of jobs, a saved software library gives manufacturers the ability to reuse previous configurations and the flexibility to make specific changes in the previous process runs.

Modutek Provides In-house Expertise and Support

With over 40 years of experience in wet bench technology and extensive in-house expertise in manufacturing operations, Modutek can help customers choose the right level of automation for their semiconductor fabrication line. Modutek offers free consultations and can discuss how different levels of automation and robotics usage can impact fabrication line performance. In general, the right level of automation for a semiconductor fabrication facility is one that improves process control and optimization and delivers long-term cost savings while improving output. Contact Modutek for a free consultation to discuss the details of your manufacturing equipment requirements.

Designing Chemical Delivery Systems to Meet Facility Requirements

Because semiconductor manufacturing facilities use a variety of chemicals to clean, etch and process silicon wafers, chemical delivery systems are critical for ensuring that operations run smoothly. Chemical handling equipment delivers or collects the required chemicals for the safe disposal of the chemical waste. Effective chemical delivery systems remove concerns about the availability and correct mixture of process chemicals and allow operators to focus on issues directly affecting silicon wafer fabrication, such as wafer cleaning, etch rates, and particle contamination. When chemical delivery systems exactly meet facility requirements, a focus on the fabrication processes lets operators optimize production and helps improve output.

Adapting Receiving and Storage of Chemicals to Facility Requirements

Chemical delivery depends on how many different chemicals a facility requires and the volume of the chemicals used. Chemical characteristics such as toxicity also have to be considered. For facilities using a variety of chemicals in varying quantities, a special area may be needed to centralize reception and storage functions.

For small volumes of chemicals, a standard drum located near the process may be the most convenient. For large volumes, receiving and storing chemical totes monitored with a load cell to track chemical use could be the best solution. For dangerous chemicals, containment of possible leaks and special safety measures may be required to ensure compliance with environmental and safety regulations. A competent manufacturer of chemical delivery and storage systems can evaluate these factors and make corresponding recommendations.

Ensuring Timely and Reliable Delivery of Chemicals to the Process

The key function of chemical delivery systems is to ensure that the required chemicals are provided in precise amounts as needed for the process. Silicon wafer fabrication steps clean and etch wafers with mixtures of chemicals that have to be delivered to process tanks. Each step requires precise quantities of chemicals delivered in sequence and at timed or process-dependent intervals. Each facility has different process steps and different chemical delivery requirements. A well-designed chemical delivery system will reliably provide exactly the right chemical in the specified volume at the correct time.

Collecting and Disposing of Used Chemicals Safely

Once a process step is complete, the chemical mixture that remains is often still chemically active, toxic and dangerous. The wafers will have been removed from the chemical bath and the used chemicals need to be safely treated or collected and disposed. For example, acids used in wafer etching are hazardous for operators, harmful for the environment and even the vapors may be dangerous.

Disposal of chemical waste has to be in accordance with local safety and environmental regulations. The chemical system can either drain the chemical waste and send it to an on-site chemical neutralization system for treatment, or to storage in a chemical collection container. Used chemicals in chemical collection containers can be picked up by service providers that specialize in chemical disposal. In either case, the chemical handling has to be carried out safely while containing any leaks or spills.

Modutek’s Expertise with Chemical Delivery Systems

Modutek has extensive experience designing and building customized chemical delivery systems. With in-house expertise in designing and supplying a full line of chemical handling equipment and systems, Modutek can evaluate a facility’s chemical delivery needs and make corresponding recommendations. If you need guidance on selecting the right chemical handling equipment and systems for your facility, contact Modutek for a free consultation.