Category Archives: Teflon Tanks

How Better KOH Etching Results Are Achieved Using Teflon Tanks

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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.

How Teflon Tanks Improve the KOH Etching Process

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How Teflon Tanks Improve the KOH Ethcing ProcessEtching silicon wafers with potassium hydroxide (KOH) is a popular process for semiconductor manufacturing because it is relatively safe compared to other etching methods and because it features good control of the etch rate. When carried out in Teflon tanks, contamination is reduced and the etch rate can be controlled.

A key factor for successful etching is to determine the required etch rate. If the rate is too fast, the KOH may etch too far into the silicon, while if the rate is too slow, the etched holes might be too shallow. Improving the KOH etching process means applying several control methods to the etch rate to ensure the resulting etched shapes are exactly correct.

Process Factors that Affect the KOH Etch Rate

The KOH etch rate in silicon wafers is influenced by the following factors:

  • Process temperature. The higher the temperature of the KOH solution, the faster KOH will etch the silicon.
  • Solution concentration. A higher concentration increases the etch rate. Normally the concentration of the KOH solution is about 30 percent, but it can vary from 10 to 50 percent, with a corresponding effect on the etch rate.
  • Doping. Doping means adding impurities to the silicon crystal. When boron is placed into the silicon crystal lattice at a specific location, etching stops in that direction. Boron doping can influence the shapes to be etched in this way.
  • Crystal lattice orientation. The silicon crystal atoms are arranged in a cubic lattice that has a greater atom density in some directions than in others. Etching is slower in directions with a higher atom density.

All four factors have to be taken into account when designing the mask to obtain the microscopic structures in the silicon. The silicon wafer has to be oriented correctly to give the different etch rates along with the different lattice directions. Doping has to be in a place where etching is required to stop and the correct KOH solution concentration has to be mixed. These are initial conditions that are established before the process starts. A target temperature can be set as well but the temperature can be varied to adjust the etch rate during processing. The ability to vary the etch rate by changing the temperature results in excellent control of the KOH etching process.

Modutek Teflon Tanks Feature Rapid Heating and Precise Temperature Control

Modutek’s Teflon tanks for KOH processing are available in a circulating or a static design. The heat source is either inline or immersed in the overflow weir. An all-Teflon liquid path reduces the possibility of contamination. The heated tanks can improve the KOH etching process with short heat-up times and precise temperature control. As a result, Modutek Teflon tanks can keep the etch rate steady by maintaining an accurate temperature set point or can allow the etch rate to be adjusted with fast and reliable controlled temperature changes.

Both models of Teflon tanks feature uniform heating throughout the baths, level and temperature limit settings, and a drain interlock. Heat up rates are 2 to 3 degrees centigrade per minute and the temperature is controlled with a precision of plus/minus 0.5 degrees centigrade. The operating temperature is from 30 to 100 degrees centigrade and a cooling refluxor with Teflon cooling coils is included.

Modutek’s Teflon tanks are available in standard sizes but can work with customers to design and build systems with custom sizes and special requirements. With their high-quality materials, precise temperature controls, and customization capabilities, Modutek’s Teflon tanks can improve the KOH etching process to deliver better semiconductor manufacturing results. Contact Modutek for a free consultation to discuss your specific process requirements.

How Process Controls Improve KOH Etching Results

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How Process Controls Improve KOH Etching ResultsWhile potassium hydroxide (KOH) etching is a versatile process for creating silicon microstructures, precise and responsive controls are required to get superior results. The KOH wet bench process is popular because KOH etches quickly and it is less hazardous than some other processes. Combined with accurate chemical delivery and reliable process controls, KOH etching can deliver exact etching dimensions and reproducible results for batch processing.

KOH Etching Can Create Complex Shapes

The KOH process is used widely because, in addition to etching quickly, it can be set up to etch at different speeds in different directions. For example, technicians may want to etch downward, into the silicon wafer, more quickly than etching in a horizontal direction. They may want to create a rectangular shape, where the long side has a different etch rate than the short side.

The etching direction is influenced by the crystal lattice orientation of the silicon wafer and possible doping of the wafer with boron. The etching speed depends on the KOH mixture concentration and temperature. To obtain improved KOH etching results, the etching process has to be set up to include all these factors and produce the desired result every time the process runs.

When the microstructures to be etched into the wafer require different etching speeds, the process uses the fact that the crystal lattice can be denser in one direction than another. Because there are more atoms to etch away in the denser direction, etching progresses more slowly. Boron doping is a way to stop etching in a particular direction. KOH will not etch areas with boron impurities, so etching stops at the doped silicon.

Once the wafer with the correct crystal orientation and doping is ready for etching, a basic etch speed can be determined with the KOH concentration. The etch speed is controlled by the KOH mixture temperature but the concentration has to be high enough for the desired etch speed.

Typical KOH concentrations can vary from 10 percent to 50 percent with 30 percent KOH by weight representing a common value. The mixture is heated to between 60 and 80 degrees centigrade and held steady at the temperature that gives the desired etch speed. With right wafer crystal orientation, doping in the right places and the correct etch speed, the microstructures will be completed in a given time.

Teflon Tanks with Precise Controls Produce Improved Output

The Teflon tanks designed and manufactured by Modutek feature the precise temperature controls and accurate support equipment that an effective KOH process requires. To etch the silicon wafer with a high degree of accuracy, operators have to make sure the concentration of KOH is at exactly the right value and have to be able to control the temperature within narrow limits.

Modutek’s wet bench equipment can deliver the KOH mixture to the Teflon tanks at the right concentration. The tank temperature controls can produce a heating rate of 2 to 3 degrees centigrade per minute, leading to rapid correction of temperature deviations. The controller accuracy is plus/minus 0.5 degrees centigrade, precise enough for excellent etching speed control.

The precise controls mean that the etch rate remains exactly at the desired level. The dimensions of the silicon microstructures are etched exactly as planned and the KOH process delivers high-quality output. Equally important is that the next time a batch is run with identical requirements and settings, the output is reproducible and the silicon microstructures are the same.

Modutek offers a complete line of wet bench processing equipment and can adapt the KOH etching tanks as well as other processing stations to meet the needs of its customers. All equipment is designed and built-in house, allowing for extensive customization and unparalleled customer support and service.

Advantages of Using the KOH Etching Process

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Advantages of Using the KOH Etching Process for Silicon EtchingThe KOH etching process uses a potassium hydroxide solution to etch silicon wafers and produce microscopic structures in the silicon. In subsequent semiconductor fabrication steps, the micro structures are used in the manufacture of integrated circuits, processors and other electronic devices.

Compared to other etching processes KOH etching is comparatively safe, etches silicon rapidly and can be tightly controlled. These characteristics are especially important for batch processing when a process step has to be reproduced precisely many times. While other chemical processes are required for specific semiconductor cleaning and etching steps, industrial plants and research facilities prefer the KOH process for general silicon etching.

How the KOH Etching Process Works

The KOH solution is prepared by adding KOH to water in an etching tank made of material impervious to aggressive chemicals. Silicon wafers are masked with silicon nitride or silicon dioxide, substances that the KOH solution does not etch. When the wafers are immersed in the KOH solution, silicon is removed from the areas that are not masked by the chemical action of the KOH etching solution.

The etch rate can be controlled by changing the concentration of the solution and by changing the temperature. The concentration is fixed once the process is established and is usually around a 30% solution by weight, but may be as low as 10% and as high as 50%. Typically the solution temperature is about 60 to 80 degrees centigrade and the etch rate increase is very sensitive to an increase in temperature.

Other factors influencing the etch rate are the crystal lattice planes of the silicon and the presence of boron doping. Different crystal lattice orientations are etched at different rates so that the crystal lattice planes influence the design of the masks and their placement. Boron doping can be used to stop the etching in a specific direction. Taken together, all the ways the etch rate can be controlled allow the creation of complex shapes in the silicon.

Controlling KOH Etching

Obtaining the desired etching results from the KOH process can be divided into two groups of control measures. The concentration, doping and lattice orientation are determined initially before the process starts and establishes itself. At that point, temperature control can still change the etching rate. The initial control measures can be put in place with the required precision, concentration and other characteristics but the temperature of the etching solution must be controlled accurately on a continuing basis.

Because the KOH etching process is very temperature sensitive, maintaining the temperature at the exact set point is important. The temperature controller must be accurate during the process and also from one batch to the next. Tight control during the etching process ensures that the etch rate remains constant while precisely keeping the same temperature for a given set point from one batch to the next ensures accurate reproducibility of process conditions and identical output across different batches.

Modutek’s Teflon Silicon Etch Tanks

Using Modutek’s Teflon tanks allows operators to fully benefit from the advantages of KOH etching. The tanks are designed with KOH etching in mind and feature a wide temperature range, tight temperature control and rapid heating. Custom sizes are available and custom installations can be designed to fit any new or existing wet bench application.

Heating in Modutek’s Teflon tanks is either in line or through an immersion heater in the overflow weir. Temperatures can be controlled to plus/minus 0.5 degrees centigrade and the temperature range is 30 to 100 degrees centigrade. The heating rate is 2 to 3 degrees per minute, depending on the size of the system, and heating is even throughout the bath. Since temperature control is a key requirement for successful KOH etching, these system characteristics allow for excellent reproducibility between batches and for the precise control needed for high quality output.

Apart from excellent temperature controls, Modutek’s Teflon tanks feature all TFA Teflon with advanced manufacturing techniques designed to minimize contamination. Options such as an auto lid feature or a condensing refluxor are available if needed. Modutek Teflon tanks are an ideal solution for KOH etching applications and the company can help select the model and options that best satisfy specific customer needs. Contact Modutek for a free consultation on selecting the right equipment for specific process requirements.

Reviewed and Approved by Douglas Wagner
President & CEO, Modutek Corporation

 

Why Teflon Tanks Are Used with the KOH Etching Process

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KOH etching is a preferred silicon wafer fabrication method because it works rapidly and reliably while handling of the chemicals is relatively safe. The process relies on a contamination-free environment and uses the temperature and KOH concentration to control the etching speed. Teflon tanks are used in this process because the Teflon is stable and doesn’t degrade. The KOH etching process controls allow accurate and repeatable temperature control for reliable fabrication results and high-quality production. KOH etching in Teflon tanks with temperature control is an excellent process for silicon wafer nanostructure fabrication in both manufacturing facilities and research environments.

How KOH Etching Works

KOH or potassium hydroxide etches silicon quickly and at a constant rate that depends on the concentration of the solution and the temperature of the liquid. In addition to these controllable variables, silicon etching is influenced by the crystal planes of the silicon and the doping concentration. These factors can be used to direct etching in certain directions and to stop etching at given points. The result is that KOH etching can produce the precise nanostructures needed as long as the crystal planes and doping are used correctly.

The controllable variables have to be kept tightly to set values and variations have to be minimized. Important factors are the maintenance of the KOH solution at the desired concentration and temperature. The Teflon tanks have to be designed to support the consistent and accurate etching necessary for defect-free wafer fabrication.

Modutek Teflon Tank Features

Modutek Teflon tanks are designed to support KOH etching leading to wafer fabrication of the highest quality. The temperature-controlled tanks are available in re-circulating and static versions and come in standard sizes for single or double carrier capacities as well as in custom sizes when required. The re-circulating tanks have an all-Teflon fluid path, and in the available custom configurations, are easy to integrate into existing fabrication lines.

Modutek Teflon tanks eliminate contamination from the tanks or fluid paths by ensuring the KOH solution only comes into contact with Teflon, which in unaffected by the corrosive chemical. In addition, Teflon welding for the tanks is carried out with advanced PFA sheet welding techniques that reduce impurities and by-products. The result is that the KOH solution stays pure.

A key element of the KOH etching process control is the initial concentration of the KOH solution and keeping it constant throughout the process step. Modutek Teflon tanks have sealed lids that minimize water loss, even during lengthy etching. Water condensing systems and de-ionized water spiking systems are available if the application requires it.

The other variable affecting the etch rate is the temperature of the KOH solution. Modutek tanks have either inline heating or immersion heating in the overflow weir. Temperature can be controlled between 30 and 100 degrees Centigrade with an accuracy of plus/minus 0.5 degrees Centigrade. Heating is rapid with an average heat-up rate of 2 to 3 degrees Centigrade per minute depending on the details of the installation. Rapid heating and tight control result in superior etching performance and consistent output.

To make operation of the KOH etching flexible and convenient, the Modutek Teflon tanks systems have standard drain interlocks and low level, high limit, and high-temperature alarms. Temperature process controllers and remote operation timers are also available.

Modutek Teflon KOH tanks are designed specifically for applications such as KOH etching and Modutek can supply custom systems specially adapted to customer requirements. Tank sizes and controls can be designed to match customer applications. Modutek can rely on its experience and expertise to supply KOH etching systems that meet the highest quality standards and deliver the best output possible.

 

How the KOH Etching Process is Improved Using Modutek’s Teflon Tanks

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Among the different approaches available to foundries that create intricate integrated circuitry on semiconductor chips, etching with potassium hydroxide (KOH) is frequently preferred for the error-free mass-production that it allows.

The improvement in precision that the KOH etching process brings to semiconductor fabrication is attributable in large part to the use of deionized water. When employed with high alkalinity in excess of pH 12, this process can be thermally adjusted for precise degrees of etching.

How does the use of potassium hydroxide improve the semiconductor etching process?

While dry semiconductor etching processes do exist, they tend to present challenges in process control. Semiconductor wafers etched in this way tend to suffer from quality control issues. Dry etching processes can be difficult to build and run, as well — toxic and explosive chemicals often seen as byproducts, after all.

Greater precision

Etching with potassium hydroxide offers greater precision, and lends itself to improved control, as well.

The fluids employed in the KOH etching process are stored in tanks built into the equipment. One of the most cost-effective and meaningful choices to make in KOH etching processes: to place Teflon tanks within the etching equipment in order to hold the fluids employed. Teflon tanks can make the KOH etching process safer than other options available.

It is possible to structure the KOH etching process in a way to easily create repeat manufacturing projects, as well. When such projects come in from different clients, fabrication units can focus their strengths on setting up the equipment, worrying as little as possible about safety or reliability.

Opting for fewer contaminants and greater cleanliness

Customization is one of the greatest most significant improvements that Modutek brings to the KOH etching equipment business — one where generic, mass-produced Teflon tanks are the norm. Modutek’s Teflon tanks are especially capable of bringing impurity quantities to levels that are impressively low. The result is greater reliability and consistency over an extended period of time.

Greater control

Modutek’s Teflon tanks come with highly customizable temperature settings. Temperature control is achieved either through in-line heating and cooling equipment installed, or through immersion in liquid tanks. It is precisely varied anywhere between 30°C to 100°C. Temperature changes dialed up our achieved at a fast rate of 2°C a minute, on average (although tank size does affect response rates).

Modutek brings customization to the table

Modutek designs Teflon tanks for the specific needs of each client installation. Whether a fabrication plant requires temperature controlled recirculating baths for their KOH etching processes or temperature controlled static baths, Modutek’s Teflon tanks deliver both freedom from water loss and freedom from concentration deficiency.

From dual heating Teflon tanks for fast and consistent water-based etching, to the installation of drains and valves that enable rapid cleanup, high-tech remote data interfaces, controllers and timers, Modutek’s clients have their choice of every advance in KOH etching.

 

How Teflon Tanks Are Used in Wet Processing Applications

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

Teflon Tank Configurations

Modutek offers three types of Teflon tanks:

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

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

Temperature-Controlled Teflon Tanks

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

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

Teflon Tank Features

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

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

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

Teflon Tank Options

Modutek tanks can be ordered with the following options:

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

Benefits of the Modutek Teflon Tanks

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

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

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

Modutek Support

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

Improvements to the Silicon Wet Etching Process

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Improvements to the Silicon Wet Etching ProcessAs a result of improvements to equipment design and materials,  silicon wet etching process controls have improved to produce higher wafer yields with reduced defects. Modutek provides silicon wet etching equipment engineered to incorporate such improvements that are designed for reliability, safety, and low cost of ownership. The wet etching products from Modutek include features that offer specific advantages and deliver improved results. Process engineers and fabrication facility managers can order customized equipment to meet their needs and to ensure they receive the process improvements they expect.

Modutek’s QFa Series High-Temperature Recirculating Quartz Baths and the Qa Series Constant Temperature Quartz Baths are designed to set the quality standard in quartz baths. Used for etching, stripping, and heating, the baths feature fast, even heating to improve process yield and minimize damage from runaway temperatures. The high-quality internally flame-polished virgin fused quartz process vessels reduce downtime and increase reliability due to longer vessel life.

Although Modutek’s Teflon tanks come in standard carrier sizes, the company will build custom sizes to match any requirement. Tank configurations are Temperature Controlled Recirculating Baths, Temperature Controlled Static Baths and Teflon Ambient Baths. Inline heating or immersion heating are available. Modutek can help design the optimal configuration for both new as well as existing systems you may already have.

Modutek’s silicon wet etching baths deliver excellent process control while retaining flexibility in installation and operation. The control system monitors the temperature of the bath to determine when adding de-ionized water is required to maintain the acid-to-water ratio. As water is lost to evaporation, the boiling point of the bath increases and the control system adds small amounts of water to the boiling liquid, ensuring that the water mixes in immediately. This method tightly controls the boiling of the chemicals and avoids “bumping.” The availability of remote metering means that the product is easy to install and Modutek can help find the best solution for any process station.

Modutek’s line of Quick Dump Rinsers can increase process efficiency by reducing rinse times and DI water consumption. The Rinsers feature state-of-the-art engineering to eliminate particle entrapment and minimize rinsing times. Dual overhead spray manifolds, a contoured vessel design and a large machined dump door ensure efficient and rapid operation.

For facilities that could benefit from using KOH etching, Modutek offers customized solutions manufactured according to customer specifications. KOH etching is a repeatable process that delivers fast etching at a low cost. Modutek’s solutions use the company’s Teflon tanks with advanced welding techniques and all-PFA material. The products can be designed to particular specifications or to be compatible with your existing wet bench equipment. Once the wet etching process is established, continual adjustments are not necessary. Modutek can integrate the new products into an existing line to deliver process improvements and increased efficiency.

Making use of improved designs or higher-quality materials can generate substantial benefits from reduced costs and better throughput. The increased ability to manufacture customized products that are optimized for a particular application can further improve silicon wet etching results. For any questions about silicon wet etching products or for help selecting the right manufacturing equipment for your requirements, call Modutek at 866-803-1533.

Using the KOH Etching Process with Modutek’s Teflon Tanks

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Potassium hydroxide-KOH etching is an efficient chemical process that allows for precise impressions to be made within a body of silicon. The process uses DI (deionized) water in combination with heavy alkalinity (pH levels greater than 12); the solution is then thermally adjusted for the appropriate degree of etching needed. This process allows for greater precision than other forms of etching when it comes to manufacturing silicon wafers.

What Are the Benefits of Using KOH Etching?

The precision KOH etching grants is very beneficial to the product’s outcome. Due to its chemical composure and procedural approach, dry etching is more apt to create physical flaws; it also can make for a more hazardous environment, as it risks the exposure of toxic — even explosive — chemicals.

KOH etching, on the other hand, is almost entirely aquatic. The liquids for the etching process are contained within Modutek’s own Teflon Tanks, meaning that exposure to hazardous chemicals is drastically reduced to create a safe environment for manufacturing. The structuring behind the process also means that it can easily be set up for repeat manufacturing; the resources required for the etching are more stable and affordable, meaning that clients can duplicate their etchings at a much more feasible rate.

How Do Teflon Tanks Bolster the KOH Etching Process?

Modutek’s Teflon Tanks are designed with the foresight to emphasize the maximum potential KOH etching can provide. Furthermore, each Teflon Tank is fashioned to cater to the specific needs of the client, regardless of unorthodoxy. In unison with wet bench equipment, these Teflon Tanks greatly reduce the impurities other methods of etching may establish, providing you with a more reliable and consistent output every time.

The Teflon Tanks can be thermally adjusted to operate between 30 — 100º C (86 — 212º F), and on average can heat up at a rate of 2 — 3º C per minute, though smaller or larger tanks may have varying thermal increase rates. Thermal output can be mustered either from inline Teflon heating, or from submersion within an overflow bank for each type of Teflon Tank. Each tank is also fitted with cooling coils that can quickly reduce the solution’s temperature.

There are two types of Teflon Tanks that support KOH etching: Temperature Controlled Re-circulating Baths (TFa Series), and Temperature Controlled Static Baths (TI Series). These two series of Teflon Tanks are designed with overlapping covers to minimize the loss of water during the etching process; they also boast the ability to eliminate concentration deficiency.

Because Modutek designs their Teflon Tanks with the client’s specifications in mind, the customization each tank receives is advantageous to the desired end result. Dual heating methods produce a quick, balanced aid to water-based etching. Drains and valves can be installed into the tanks for safe and easy clean-up. Remote timers, controllers, or even a data interface can be equipped to make a simple process even simpler.

When compared to other forms of etching (whether wet or dry), Modutek’s support of KOH etching produces more precise and affordable results in a safer and more expeditious work environment. Teflon Tanks can be produced individually or en masse depending on the output the client is in need of. Each tank can also be fitted with a number of practical options that can improve the etching process dramatically.

No client should work with an environment or product that diminishes the quality of their manufacturing process; customization leads the way for an innovative and effective product. Modutek’s support of KOH etching in their catalytic Teflon Tanks will provide exceptional results for clients that use this process.