How the SPM Clean Process is Supported in a Wet Bench Process

How the SPM Clean Process Is Supported in a Web BenchEditor’s Note: This article was originally published in Oct 2016 and has been updated with additional information and reposted in May 2023.

Semiconductor manufacturing involves multiple processing steps which include cleaning silicon wafers. The sulfuric peroxide mix (SPM) cleaning process is widely utilized in semiconductor manufacturing. The process utilizes a mixture of approximately 3 parts sulfuric acid to 1 part hydrogen peroxide which is highly effective at eliminating organic and inorganic contaminants from semiconductor wafers. The SPM process is typically performed in wet benches specifically designed for this cleaning process.

The SPM Clean Process

Sulfuric acid in the SPM solution reacts with organic contaminants like photoresist and residue, while hydrogen peroxide oxidizes and removes inorganic contaminants like metal ions and particles from semiconductor wafers. This reaction generates heat which helps to accelerate cleaning. Process engineers using the SPM process in semiconductor manufacturing need to make sure that the chemical ratio and temperature are maintained within safe limits and that the solution and wafers are contained safely in impervious baths. During the process concentration levels may vary from 3 to 1 to a maximum of 7 to 1 and the temperature used may be as high as 140 degrees centigrade. When the solution operating values are chosen, the baths should be maintained at those concentration and temperature values to keep the strip rate uniform.

Advantages of SPM Clean

SPM Clean offers several advantages over other cleaning methods. Its key advantage lies in its effectiveness at removing organic and inorganic contaminants simultaneously. The process is relatively quick usually taking just a few minutes. In addition, the SPM clean process does not damage or etch the substrate beneath, making it ideal for sensitive materials like silicon dioxide and silicon nitride.

Equipment for the SPM Process

SPM cleaning solutions are typically applied in a wet bench designed specifically to facilitate this cleaning method, typically composed of materials compatible with SPM solutions like polypropylene, Teflon, and quartz. Wet benches come equipped with safety features such as fume hoods, exhaust systems, and emergency shutoff switches to help minimize chemical exposure. For consistent and reliable results, SPM clean process equipment typically features process control and automation features to facilitate consistent operations. SPM solution concentration, temperature, and flow rate can all be carefully managed in order to ensure an efficient cleaning process. In addition, automated wafer handling systems may also help minimize contamination risks while improving process efficiencies.

Safety Considerations

To ensure the safe and effective implementation of the SPM Clean process in wet benches, certain practices should be observed. These include adhering to safety procedures, performing regular equipment and tool maintenance checks, optimizing cleaning process performance, and complying with local regulations for waste management and disposal.

Using the SPM Clean Process in Modutek’s Wet Benches

Modutek provides manual, semi-automatic, and fully automatic wet bench systems that support the SPM clean process. Wet Bench systems are available in a wide variety of configurations as well as in custom designs. The fully automated stations use Modutek’s in-house software for automatic process execution with high accuracy, reliability, and repeatability. The semi-automated stations can achieve similar results with robotic controls at a lower cost. The manual stations have the same safety and process features without the cost of automation.

Quartz Recirculating Baths

To work well, the SPM solution must be heated rapidly in a bath that can withstand high temperatures and that will not react with aggressive chemicals. Heating must be even and controlled within a narrow range. At high temperatures, hydrogen peroxide decomposes and the solution must be spiked with more peroxide to maintain its concentration.

Quartz recirculating baths fulfill all these requirements. The quartz can be manufactured in a pure enough form to withstand the temperatures and corrosion while the recirculation allows tight control of concentration with the addition of chemicals as required.

This spiking allows operators to use the solution for a longer period of time rather than discarding the solution when the concentration falls below acceptable levels. Re-using sulfuric acid for as long as possible reduces costs and is desirable from an environmental point of view as well.

Modutek Series QFa Series Quartz Baths

Modutek’s quartz baths support the SPM Clean process and satisfy key conditions for high safety and reliability as well as low cost of ownership. The tanks are made of semiconductor-grade flame-polished quartz and are insulated with high-density alumina-silica fiber rated to 1260 degrees centigrade. The four-sided heating element promotes fast, even heating and the seamless sloped flange and the dual safety snap switch help ensure safe and convenient operation.

The quartz baths have an operating temperature range of 30 to 180 degrees centigrade and they feature a standard heat-up rate of 2 degrees centigrade per minute. The operating temperature can be controlled to within plus/minus 1-degree centigrade and a liquid level sensor is available as an option.

Standard tanks are available in dimensions ranging from 7.75 to 21.5 inches inner side length and in square and rectangular formats. Depths range from 6.75 to 14.5 inches and available heaters are rated 2 to 6 KW. Modutek can design systems with custom vessel sizes to satisfy specific requirements.

The Bottom Line

Modutek’s wet benches and quartz baths are designed with low cost of ownership in mind while emphasizing features that reduce errors and improve reliability. Semiconductor manufacturers using the SPM process can achieve higher throughput and better output quality using Modutek’s equipment. Contact Modutek for a free consultation or quote on wet bench equipment to support your wafer cleaning processes.

How Automated Controls Improve Silicon Wafer Manufacturing

How Automated Controls Improve Silicon Wafer ManufacturingPrecise automated controls that are incorporated into wafer manufacturing equipment help manufacturers meet the challenges of higher component densities and compliance with environmental regulations. They provide excellent repeatability and accurate chemical dosages that precisely control the etch rate and the cleaning and stripping processes. Chemical neutralization and disposal are handled automatically with document generation to prove regulatory compliance.

In addition to delivering improved process control, the automation software can easily be customized for specialized process requirements or updated to reflect process changes. From the user inputs through to process equipment, the different components of automated wafer fabrication equipment work together to improve manufacturing outcomes.

An Intuitive User Interface Helps Operators Control the Process

A good user interface shows critical process variables and the status of necessary equipment. Operators can see how the process progresses and intervene to activate or shut down components if necessary. The interface can easily be updated when process requirements change or equipment is added. For fully automated stations, the process runs by itself after the operators select the sequence and set the initial conditions via the user interface.

Modutek automated stations use a touch screen with a graphical user interface (GUI). Operators see visual representations of the process and can control equipment from the screen. Because Modutek designs and programs the underlying software in-house, the company can easily change and update the GUI.

Automated Controllers Translate GUI Commands to Equipment Operation

Automation controls timed command sequences or keep process variables at the required set points. Sequences are programmed with Programmable Logic Controllers (PLCs) that output a sequence of commands when the operator issues the initial input. PLCs are programmed as a chain of outputs triggered by elapsed time or automated inputs. The chains are easy to program and change if needed.

Automation of process variables includes controllers for temperature, pressure, flow, or level. Modutek can integrate third-party controllers such as Omron or Allen Bradley for higher-level automation, such as machine control or special functions. This capability also allows Modutek to integrate its equipment into existing installations.

Data Logging Helps to Evaluate System Performance

When the Modutek automated stations are programmed to output key variables, the data can be assembled into reports helpful in evaluating performance and monitoring the program logic controls. The data can be collected over Ethernet and viewed remotely. Automated logs can be used to check values such as chemical use, output quantities, output yields, and chemical disposal details. Feedback from data logging is key to the optimization of the overall process.

Optional Equipment Interfaces Increase Application Flexibility

Modutek’s automated wafer fabrication equipment uses an optional interface that allows it to work with existing systems and components from other manufacturers. The SEMI Equipment Communications Standard/Generic Equipment Model (SECS/GEM) developed by the Semiconductor Equipment and Materials International (SEMI) organization governs the interaction of the software running the automated controllers and the semiconductor manufacturing equipment. Under the SECS/GEM standard, Modutek can customize its systems to meet customer requirements for updating its process lines or adding new equipment.

As a leading semiconductor equipment manufacturer, Modutek continuously innovates on equipment and automation. The company can supply individual pieces of equipment or provide turnkey installations. Modutek ensures its equipment meets customer needs and performs as expected in both cases.

Easy to Install Wet Processing Equipment for R & D

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.

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.

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.

How Process Controls Are Improved with Automated Wet Bench Equipment

how-process-controls-are-improved-with-automated-wet-bench-equipmentWhen semiconductor manufacturing is automated, tight process control can improve overall facility performance. An optimized manufacturing process can reduce consumption of consumables and production results are more uniform. Once a batch has run successfully, an automated process ensures that it will run the same way for subsequent batches. With good design, automation reduces silicon wafer handling and particle contamination. A wet process equipment provider has to be able to customize the automated functions to meet the needs of the application, but once it is set up, the process can run with a minimum of amount of monitoring from an operator.

Automation Can Reduce Chemical Use

An optimized automated process uses the least amount of chemicals required to carry out the etching or cleaning function and it continues to do so reliably. Spills and human error are eliminated while chemical use is tracked. Chemical treatment prior to disposal is closely monitored and neutralizing chemical use is reduced to a minimum while still ensuring compliance with environmental regulations. When overall chemical use is reduced, the cost savings can be substantial.

Output Quality is Improved with Automation

As semiconductor components and micro-structures become more tightly packed, they are more sensitive to dosage variations and process parameter inaccuracies. Processes such as etching are often dependent on temperature and chemical concentration. The timing of the process steps is critical in obtaining exactly the required etched pattern. Fully automated wafer fabrication equipment has these variables programmed in and runs the process accurately and the same way each time. Semiconductor component output is consistent with fewer defects and rejections.

Automated Neutralization Reduces Environmental Impact

Using an automated system to treat, neutralize and discharge chemical waste has several advantages. Waste from wet process manufacturing can be toxic and hazardous so human error during neutralization can have severe consequences for the environment and surrounding communities. Automation can ensure that acid and solvent chemical waste is neutralized and an automated system can block discharge if the output pH is not within predefined limits. Because all chemical use and discharge is tracked, compliance with environmental regulations can easily be demonstrated.

An Experienced Provider Can Customize Both Equipment and Automation

Depending on what kind of semiconductor components are being produced, a manufacturing or research facility may require highly customized equipment to carry out the process steps required. The automation has to flexible enough to accommodate custom process steps and the equipment provider has to be able to program the automation accordingly. Ideally, an experienced provider will work with customers to exactly define what is needed and then build the wafer fabrication equipment with the required automation. Such cooperation can result in equipment and controls designed and built for the specific purpose and delivering exceptional performance for the customer.

Modutek Designs and Builds Its Own Equipment with Automation

Modutek designs and builds its own equipment in-house based on extensive experience in wet process technology. This leaves Modutek in an ideal position to customize wafer processing equipment as needed to meet customer requirements. Because the expertise is in-house, Modutek engineers and technicians can adjust designs to reflect customer needs. This ability extends to the wet bench stations as well as to the automation that runs them.

Modutek’s SolidWorks Simulation software calculates precise dosages and process parameters and is also developed and supported in-house. Modutek can offer assistance for custom design of process stations, supporting equipment, and software to ensure customers get the systems they need. After the process line is built, installed, and tested, Modutek can provide full support with their own in-house specialists to make sure the automated semiconductor manufacturing process continues to operate as expected.

5 Important Things to Know Before Buying a Wet Bench Station

5 Important Things to Know Before Buying a Wet Bench StationWet bench semiconductor manufacturing has many variations and applications often have unique features. Before buying a wet bench station, there are several main things to look at before deciding what equipment is best suited for a specific manufacturing task. Options include the type of station, how it operates, how it receives its chemicals and what specialized or custom features are required. When a prospective supplier has extensive experience and the required expertise as well as offering a complete line of wet bench equipment and customization as required, the selection becomes easier. Five main things influence which of the available wet benches to buy. Knowing these five things helps determine which station satisfies the manufacturing application requirements.

1. Different Types of Wet Process Stations Have Different Advantages

Types of wet benches include a standard white polypropylene construction for acid and base process applications such as KOH and RCA clean. Solvent application wet benches for processes such as acetone, IPA and photo resist stripping have a stainless steel construction. Stations are available with a dry-to-dry process and can include a chemical fume hood. An experienced supplier can advise on the different options and the customization possibilities.

2. The Degree of Automation Depends on the Application

Manual stations are best suited for initial development work when the main process parameters are not yet known. Manual stations can be used to develop a process framework. Once the overall process is set, semi-automatic stations can be used to program the fixed parameters to run automatically while operators retain manual control of some variables for optimization purposes. Once the process is fully developed, fully automated stations can be used to run the productions line and increase throughput.

3. Chemical Delivery Systems Improve Process Control

Chemical delivery systems run and monitor chemical storage, delivery to the process and disposal of chemical discharge. They minimize waste and reduce spills. Chemical delivery systems are recommended for applications that rely on highly accurate dosages of specific chemicals during the manufacturing process.

4. Rinsing and Drying are Critical for Avoiding Particle Contamination

Reduced particle counts on wafers improve process yields because particles can cause product defects. Special configurations such as the combined rinsing and drying station and the quick dump rinser improve process efficiency and reduce the particle count. Depending on the wet process application, such rinsing and drying configurations may improve overall facility performance.

5. Special Custom Functionality Can Be Built Into Standard Stations

Semiconductor equipment manufacturers that build their own wet process stations in house can add custom functionality when an application requires it. For example, an application may include etching of aluminum layers on a wafer and a special vacuum metal etcher may have to be incorporated in the wet bench process. Some applications require an especially low particle count and wafers may have to be cleaned with Megasonic equipment to dislodge and remove the tiniest particles. Such specialized custom functions work best when a custom design integrates them into the rest of the wet bench process.

Once customers are aware of these five pieces of information, they can proceed to select a supplier that can satisfy them on all five points. They will then be able to specify the kind of performance they want to achieve and help make sure that they get the equipment they need.

Modutek Builds Their Own Equipment to the Highest Standards

Modutek design and build their own equipment in house and can customize wet process stations as required. Their specialized modules include the combined rinsing and drying IPA dryer, the quick dump rinser and the Megasonic cleaner. The company can help customers with all five of the listed points and ensure the purchased wet benches meet their needs.

Improving Wafer Manufacturing Processes with Automated Equipment

Improving Wafer Manufacturing Processes with Automated EquipmentAutomated wafer fabrication equipment can improve semiconductor manufacturing facility performance, but all the associated process settings must be programmed properly. Before the manufacturing process can be implemented on a fully automated wet bench station, the settings, timing and other parameters have to be fine tuned. As circuit geometries and micro-structures become smaller and more tightly packed, the chemical concentrations, temperature levels and timed intervals affecting the etch rate become more and more critical. Fully automated equipment can precisely and reliably run a semiconductor manufacturing process once the correct variables are determined and programmed.

Manual Operation Can Determine the Settings for the Process Variables

Once wafer fabrication processes such as KOH etching are chosen, the process variables can be selected. Etching can be either isotropic or anisotropic and etching speed or precision can vary. Other factors may come into play as well. Initially it makes sense to run the new process on a manual station so that the process results for rough settings of basic variables such a concentrations, temperature and timing can be determined. These variables can then be adjusted to get an initial and acceptable process result.

Semi-Automatic Operation Can Fine Tune the Process

After determining the rough settings of the basic variables in manual operation, transferring to semi-automatic operation to optimize the process steps can save time. Those variables that will no longer change can be programmed into the semi-automatic software control while the others can be adjusted manually to get the best process result. In this way, as each process step is optimized, it can be programmed so that when optimization is complete, the process is ready to run on fully automated wafer processing equipment.

Fully Automated Operation Improves Semiconductor Manufacturing Facility Performance

Fully automated wet process stations for which the process has been optimized in manual and semi-automated operation can help improve overall production facility performance in the following ways:

  • Programmed settings ensure that the process is repeatable for different batches
  • Use of wet processing simulation software during optimization helps ensure accurate process parameters
  • Full automation eliminates human error
  • Precise dosages of chemicals and accurate timing results in fewer defective products
  • Throughput and wafer yields are increased

The programmed settings can be used again to get an identical result and they can be used for similar applications with minor adjustments. Instead of relying on operators to prepare etching baths, the fully automated station mixes the required chemicals quickly, safely and reliably, always the same way and without waste or spillage. The result is precise control over the process steps, fast execution without delays and high output quality.

Improved Output Relies on Optimized Software and Fully Automated Stations

Using an optimization strategy with manual and semi-automatic operation and running the optimized process on fully automated wafer fabrication equipment can lead to continuous improvement in semiconductor manufacturing operations. As new processes are brought online and optimized, they replace older versions that may not use chemicals as efficiently, may rely on some manual input or may not have the same precise and reliable execution as the fully automated stations. Tailor-made software working with fully automated wet process equipment can result in such continuous improvements.

With 40 years of experience in wet process technology and extensive in house expertise from manufacturing its own equipment, Modutek is ideally situated to supply fully automated equipment that improves semiconductor manufacturing output. The company has a complete line of standard and custom-built wet process equipment and the SolidWorks software used to calculate process parameters is programmed in house. Working closely with its customers, Modutek designs and builds its fully automated stations and programs the corresponding software to help them meet their goals for continuous improvement. Contact Modutek for a free quote or consultation on selecting equipment that supports your specific manufacturing process requirements.

How Wet Bench Stations Are Designed for Ergonomics and Safety

How Wet Bench Stations Are Designed for Ergonomics and SafetyTo etch and clean silicon wafers, wet bench stations use aggressive and toxic chemicals that have to be handled carefully. Ergonomic design ensures that employees don’t have to perform risky or strenuous maneuvers in normal operation of the facility. To load trays, control processes and dispose of waste, employees should not have to lift especially heavy weights, stretch to the limits of their reach or perform repeated strenuous actions. The Semiconductor Equipment and Materials International (SEMI) S8-0712 – Safety Guidelines for Ergonomics Engineering of Semiconductor Manufacturing Equipment can help manufacturers design equipment for comfortable and safe operation.

Key safety aspects of semiconductor equipment manufacturing include safe chemical handling and fire prevention. The FM 4910 specification and the Cleanroom Materials Flammability Test Protocol help manufacturers avoid using flammable materials in their equipment. Wet bench stations that adhere to these guidelines provide a better and safer working environment.

How Modutek Design Wet Bench Stations for Ergonomic and Safe Operation

Modutek designs its wet bench chemical stations according to the SEMI S8 guidelines and minimizes the use of flammable materials in its designs. Examples of safe and ergonomic

design measures applied by Modutek include the following:

  • Wafer holding trays are easy to load
  • Operator interface is on a swing arm
  • All stations are built around your ergonomic requirements

Ergonomic and safe design means that operators must be able to load equipment without strain. The wafer holding trays on Modutek’s wet benches can move to the front on robot arms that position the trays for optimal loading and unloading. Operators don’t have to stretch and can perform this often repeated action with a minimum of effort.

Operators have to be able to see the operator interface while monitoring the process. The interface monitor is usually off to the side of the wet bench station. The interface monitor is mounted on a swing arm that allows operators to adjust the position where they can view it while monitoring the process. The interface mounting arm can rotate and tilt to an ideal position and then can be locked with one hand. The operator can continue working while adjusting the interface monitor and doesn’t have to assume any unnatural positions.

All of Modutek’s wet bench stations are built and designed around your ergonomic and process requirements. Modutek does not sell stations which customers order from a catalog. Wet bench stations are built based on a customer’s specifications and incorporate features for ergonomic safety and repeatability. Besides ease of use Modutek also designs each station around your facility requirements. When the station is delivered all facility connections are pre-approved so your system will be up and running in a very short time. All of these added features save customers time and money.

In addition to these specific examples, Modutek applies ergonomic design principles and safety features across its full product line of wet process equipment. All its wet bench chemical stations satisfy safety regulations and are designed to keep employee physical effort to a minimum.

Equipment That Meets Ergonomic and Safety Guidelines

Modutek’s extensive line of wet process equipment and wet bench chemical stations are all designed according to the latest applicable ergonomic and safety guidelines. When customers need special equipment, Modutek can design customized systems to satisfy specific requirements. In that case, ergonomic and safety features are customized as well to make sure the special equipment meets or exceeds the guidelines.

Older equipment is often not compliant with new regulations. When that is the case, it’s a good time to purchase new or upgraded equipment. Whether new or an upgrade, the equipment comes with improved ergonomics and safety features. When employees work with reduced physical stress and feel safe in the workplace, employee morale and job satisfaction increases. If you need help selecting a wet bench station for your process requirements and also all ergonomic and safety regulations, contact Modutek for a free quote or consultation at 866-803-1533 or email modutek@modutek.com.