Category Archives: Silicon Wafer Cleaning Equipment

Single Wafer Processing Spurs Demand for Wafer Cleaning Equipment

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Wafer cleaning equipment suppliers have to invest heavily in research and development to keep abreast of rapidly changing technologies and changing market conditions. Single wafer processing is one such change factor, spurring demand for wafer cleaning equipment and promising a rapid increase in market size. The wet process equipment supplier market is characterized by high barriers to entry since it requires substantial initial investment with high continuing costs. On the other hand, single wafer processing in mini-fab operations is very attractive due to flexibility and the speed with which a single wafer can be processed. As a result, the market may see additional entrants while existing suppliers try to keep up with the anticipated growth.

Wafer Cleaning Equipment Market Details

The global wafer cleaning equipment market size was about US $ 4 billion in 2016 and it is expected to grow to over US $ 7 billion by 2024. While semiconductor demand generally is fueling this growth, the use of single wafer processing is one of the factors that is behind the increasing demand for semiconductor cleaning equipment. Mini-fab facilities feature short cycle times and production lines that allow semiconductor manufacturers to quickly meet changing market conditions.

Single wafer processing uses ozonized water and hydrofluoric acid in single spin technology to reduce cycle times and increase output flexibility. As increasing numbers of operators jump into this segment of the semiconductor manufacturing industry, the demand for wafer cleaning equipment is skyrocketing.

Another factor in cleaning equipment market growth is the market for printed electronics. The technology creates electronic devices by printing on substrates and requires clean wafers as an input. Its primary advantage is low cost for high volume and the outputs are inexpensive, low-performance items such as RFID tags and smart labels.

The combination of single wafer processing and the high volume expected for printed electronics means that the almost doubling of market size over the next seven years is realistic. When electronic tags proliferate in transportation and retail and processors from single wafer mini-fabs become common in many industries that are not high users of electronics at present, the need for wafer cleaning equipment as an input for these market segments becomes clear.

Single Wafer Cleaning Techniques

Single wafer processing is only competitive when the cycle times for individual wafers are low and the output quality is at least comparable to wet batch processing. Single wafer spin processing can be used to etch silicon and provide a wet process for mini-fab single wafer cleaning. Spin processing can limit etching to one side of the wafer and can be used for wafer thinning. Single wafer cleaning is often carried out with megasonic cleaning because this method dislodges the tiniest particles and results in a low particle count for the finished substrate. As semiconductor manufacturers embrace single wafer processing, single wafer cleaning equipment is being brought out in the market.

Some single wafer processes are attractive because they deliver better results than traditional processes. Megasonic cleaning in particular can reduce particle counts for the smallest particles. The cleaning method uses megasonic sound waves in the cleaning solution to generate cavitation bubbles. When the bubbles collapse due to changing sound pressure they release energy that can free tiny particles from the substrate surface. Particle counts are often lower than with chemical cleaning methods.

Modutek’s Silicon Wafer Cleaning Equipment

Modutek has over 35 years of experience in providing the latest state-of-the-art silicon wafer cleaning and processing equipment. The company can help customers with advice on semiconductor manufacturing equipment and offers a complete line of wet processing systems. Modutek is ideally situated to benefit from the increased demand for silicon wafer cleaning equipment.

 

 

How Megasonic Cleaning Improves the Silicon Wafer Cleaning Process

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How Megasonic Cleaning Improves the Silicon Wafer Cleaning ProcessAs silicon microscopic circuits and structures shrink in size, the elimination of contaminants from becomes increasingly important. When silicon wafer cleaning is effective, it removes particles as small as 0.1 µm to prevent them from affecting the silicon fabrication process. Traditional wafer cleaning with chemicals may leave some of the smallest particles in place and production line output quality can suffer. The semiconductor components produced may be of inferior quality or fail completely. Megasonic cleaning with sound waves in the MHz range generated in a water cleaning solution can remove particles down to 0.1 µm in size and improve cleaning performance.

How the Megasonic Process Cleans

The Megasonic Cleaning System consists of a high-frequency generator, transducers that convert the electric signal from the generator to sound waves in the water, and a cleaning tank to hold the cleaning solution and the silicon wafers. Sound waves in the MHz frequency range travel through the cleaning liquid and generate microscopic cavitation bubbles in the low-pressure wave troughs. When the bubbles collapse in the high-pressure wave peaks, they produce tiny jets of water.

When the bubbles collapse near a wafer, the resulting jets hit the silicon and dislodge any particles adhering to the surface. The particles are carried away by the water currents and the microscopic bubbles are so numerous that all surfaces are cleaned. The bubbles and the cleaning effect are present throughout the liquid and they penetrate into holes, crevices and microscopic structures, cleaning completely.

Megasonic Cleaning Benefits

In addition to cleaning silicon wafers and removing microscopic particles more effectively than traditional cleaning methods, Megasonic Cleaning provides several other benefits over the use of chemicals. The rise in output quality is accompanied by lower costs, a safer process environment and shorter process times.

When a semiconductor fabrication facility uses fewer chemicals for cleaning wafers, costs decrease. The facility has to purchase smaller amounts of chemicals, storage costs are lower and costs for disposal are less. Depending on the process, Megasonic Cleaning may allow a facility to eliminate certain chemicals completely, resulting in even higher savings.

The Megasonic Cleaning process is safe and environmentally friendly. The megasonic waves and the cleaning solution do not present any danger to equipment or operators who can set a timer and come back when the cleaning process is finished. The water-based solution is not toxic and does not require special disposal. Compared to chemical cleaning, the storage and handling of Megasonic cleaning materials is safe and easy, power consumption is lower and less water is required.

Modutek’s Megasonic Cleaning System

The Modutek Megasonic Cleaning System was developed together with ultrasonic technology leader Kaijo Corporation to reflect the specific demands of silicon wafer cleaning. The high operating frequency in the MHz range ensures gentle but effective cleaning of delicate materials without pitting the silicon surface or damaging the silicon wafer structures.

Modutek’s partnership with Kaijo lets the company offer an integrated system that features the Quava Megasonic generator and transducer within Modutek’s cleaning baths. Megasonic’s baths are available in the indirect heating MSI series that can heat the cleaning solution up to 140 degrees centigrade while the direct heating MSD series can heat the cleaning solution up to 70 degrees centigrade. Both baths are ideal for submicron particle removal with a high power density and high efficiency.

The Megasonic System is available with 600 W, 900 W and 1200 W power ratings at the standard 950 kHz frequency. Frequencies of 200 kHz, 430 kHz, 750 kHz and 2 MHz are also available for applications that require the more robust cleaning action from the lower frequencies or for very delicate components at the higher frequency. In any case, Modutek can advise customers to make sure they select the ideal Megasonic Cleaning configuration for their specific silicon wafer cleaning applications.

Silicon Wafer Strip Solutions for Wet Processing Equipment Applications

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Silicon Wafer Strip Solutions for Wet Processing Equipment ApplicationsModutek’s extensive experience in delivering wet processing equipment allows the company to meet the particular needs of each customer. Its equipment can support a wide variety of wet bench processes and its extensive range of products can be customized to solve specialized problems for particular applications. For silicon wafer strip solutions, the company can deliver equipment to support the following applications:

Silicon Nitride Strip

The silicon nitride strip process removes silicon nitride from silicon wafers containing integrated circuits in a hot acid bath. Key factors for a high quality result are the selectivity of the bath strip solution and the repeatability of the process variables. The selectivity of removing silicon nitride while leaving silicon oxide intact must be high and the process must always deliver the same results for the same inputs.

The Modutek Nb series silicon nitride etch bath monitors bath temperature while adding DI water to maintain the acid to water ratio. The process can be tightly controlled to give excellent consistency resulting in the desired selectivity and the required repeatability.

Resist Strip

Modutek offers an advanced ozone cleaning process for photoresist strip without the use of harsh, expensive chemicals. The ozone cleaning process can strip, etch or clean silicon wafers at a lower cost than conventional technology while using an environmentally friendly and safe process.

Oxide Strip (Buffered Oxide Etch – BOE) 

The F series filtered sub-ambient circulation bath for BOE applications can cut down on acid consumption while reducing particles and improving yields. Specifically designed for BOE applications, the Modutek F series bath delivers excellent performance with a large number of options available to meet specific process requirements.

Solvent Based Resist Strip 

Modutek’s SFa series temperature controlled stainless steel recirculating baths can handle a wide variety of solvents. The baths all meet Class 1 Div 1 Group D requirements and can handle solvents such as IPA, acetone and resist strip solutions. The vessels are 316L electropolished stainless steel designed for long vessel life and operate at a temperature of up to 100 degrees Celsius. Available in a range of sizes as well as with custom dimensions, the baths are designed to handle all solvent applications.

SPM Photo Resist Strip

For photo resist strip using the sulphuric acid / hydrogen peroxide mixture SPM process, the Modutek QFa high temperature recirculation quartz baths are an ideal solution. They feature fast, even heating in a seamless, sloped flange design. Operating temperature range is 30 to 180 degrees Celsius with an approximate heat up rate of 2 degrees per minute. Process temperature control can provide an accuracy of up to plus/minus 1 degree Celsius. The quartz bath vessel is made of boron-free internally flame polished virgin fused quartz and Modutek can supply a wide range of standard and custom sizes.

Wet Processing Strip Solutions

Processing engineers considering various silicon wafer strip solutions can be confident that Modutek can supply the appropriate wet processing equipment for their application. The company has been in operation for over 35 years and provides an extensive product line of semiconductor manufacturing equipment. Their experience and expertise allows them to offer both standard equipment for common applications as well as customized solutions for applications outside the norm.

With Modutek, engineers can choose the wafer strip process they want to use, from conventional SPM, solvent or silicon nitride wet processes to the new advanced ozone technology. They can decide which is the most appropriate for their particular application. Modutek can provide recommendations on the wet processing equipment needed and also offer different options when applicable. For a free consultation or quote on selecting equipment for specific wafer strip applications call Modutek at 866-803-1533 or email Modutek@modutek.com.

How the Ozone Cleaning Process Improves Silicon Manufacturing Yields

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How the Ozone Cleaning Process Improves Silicon Manufacturing YieldsA process that uses ozone with water or with a mild acid can clean, strip and etch wafers more rapidly and at lower cost than traditional processes. Modutek’s proprietary Advanced Ozone Cleaning Process eliminates the use of expensive chemicals while improving process performance and reducing environmentally harmful waste.

Modutek provides custom designed equipment to meet the specific requirements of customers and offers an ozone cleaning process as a solution for better silicon wafer manufacturing yields. The patented technology can replace traditional methods that use expensive chemicals and high temperatures with a room-temperature process that is environmentally friendly.

How the Ozone Cleaning Process Works

Modutek’s ozone cleaning process provides cleaner silicon wafers with reduced particle counts. For example, in Modutek’s DryZone solvent gradient dryer, the patented process rinses substrates with deionized water to remove water-miscible inorganic impurities and then exposes them to ozone in an ozone chamber. All traces of organic materials are converted to carbon dioxide. The resulting substrate surfaces are free from particles, moisture and trace organic materials and are stable hydrophilic surfaces.

For silicon wafers, the surfaces are Si-O terminated. If hydrophobic, Si-H terminated surfaces are required, a ten second post-ozone process can complete a conversion. Because the dryer uses reactive chemistries, it is particle-reducing rather than just particle-neutral.

In Modutek’s Organostrip process, wafers are exposed to an ozonated organic solvent at room temperature. The company’s technology produces very high ozone solubility in the liquid. The process results in a fast resist removal and it is compatible with all metals tested, including aluminum, copper, gold, tantalum, titanium and tungsten.

In all the Modutek ozone cleaning processes, the exact chemistry is delivered to the point of use in compact equipment that requires fewer steps and a smaller number of tanks than conventional wet benches. In contrast to traditional solvent processes, the ozone process solution has a longer useful lifespan and results in a more benign discharge. Available ozone processes include resist removal, surface preparation and final clean.

Advantages Compared to the Piranha Process

A commonly used conventional acid process is the sulfuric acid and hydrogen peroxide based Piranha process. Key advantages of the ozone cleaning process over the Piranha process include:

  • More rapid processing: Batches of 100 wafers and a rate of 6 batches per hour per process tank allow silicon manufacturing facilities to achieve a higher throughput.
  • Better compatibility: The Piranha process is not compatible with most metals while the Modutek ozone cleaning process has broad compatibility.
  • Fewer particles: The number of particles left on wafers processed with the Modutek ozone cleaning systems is extremely low while Piranha leaves particles on the surfaces.
  • Better safety: The Piranha process operates with highly corrosive chemicals heated to 130 degrees C. The Modutek ozone cleaning systems work at room temperature without harsh chemicals.
  • Lower equipment cost: With fewer tanks and process steps, the Modutek ozone cleaning systems can cost substantially less than a Piranha installation
  • Lower operating costs: Piranha process chemicals are up to twice as expensive as Modutek ozone cleaning chemicals. The total cost of ownership of a Piranha installation is much more than that of an ozone station.

Modutek can evaluate the needs of a silicon manufacturing facility and offer appropriate solutions. The new ozone technology increases manufacturing yields by reducing contaminants and can reduce overall costs. If you want a free consultation or quote on using Modutek’s ozone cleaning process to improve your manufacturing yields, call 866-803-1533 or email modutek@modutek.com.

Silicon Wafer Cleaning Solutions for Wet Processing Applications

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Silicon Wafer Cleaning Solutions for Wet Processing ApplicationsModutek designs and delivers standard and customized silicon wafer cleaning equipment for semiconductor manufacturing facilities and research labs. Supported cleaning processes include RCA clean, Standard Clean 1 and 2, Piranha etch clean, and pre-diffusion clean. The company has specialized in silicon wafer cleaning equipment for over 30 years and emphasizes effective and efficient contaminant and particle removal to ensure high yields, improved throughput and high quality output.

RCA Clean

The RCA clean process is based on a cleaning method developed at RCA Corporation to remove organic residue from silicon wafers. The cleaning solution is made up of 5 parts water, 1 part 27% ammonium hydroxide and 1 part 30% hydrogen peroxide. It removes organic contaminants and leaves a thin layer of oxidized silicon on the surface of the wafer.

Standard Clean 1 and 2

The RCA cleaning process is often carried out in two steps called SC1 and SC2. The SC1 step uses the APM (ammonia/peroxide mixture) solution of the RCA cleaning method to remove organic matter and particles. The SC2 cleaning method uses a solution of hydrochloric acid and hydrogen peroxide or HPM (hydrochloric/peroxide mixture) to remove metallic ions. The two steps prepare the silicon wafer for further processing.

Piranha Etch Clean

The Piranha etch clean removes large amounts of organic material. It is used when there are visible organic contaminants such as photoresist or other hard to remove organic materials. It uses the Piranha solution, made up of a mixture of hydrogen peroxide and sulphuric acid, to clean silicon wafers and hydroxylate surfaces making them hydrophilic. Typical mixture ratios are 3 parts of sulphuric acid and 1 part of 30 percent hydrogen peroxide or higher sulphuric acid ratios of up to 7 to 1. The mixture is highly corrosive and has to be handled with special care.

Pre-Diffusion Clean

The pre-diffusion clean is the final step before the silicon wafer goes into the diffusion furnace. The wafer surfaces must be free from particles and from metallic and organic contaminants. Native oxides or chemical oxide films may have to be removed.

Depending on the nature of the contaminant, a variety of aggressive chemicals, including those from the above cleaning methods, may be used to achieve clean surfaces. Pre-diffusion cleaning is critical because particles or contaminants on the wafer surface may affect the diffusion process and result in defective or low-quality semiconductor output.

Modutek’s Silicon Wafer Cleaning Equipment

Modutek’s dual tank rotary wafer etching system provides a convenient silicon wafer cleaning solution in a compact design. Once the operator loads the wafers and closes the fume door, the wafers are moved to a chemical process tank. After a pre-programmed agitation cycle, the wafers are transferred to the quenching tank where they undergo a set series of rinse cycles. When the set number of cycles is reached, an alarm sounds and the operator can remove the wafers.

Cleaning stations can be manually operated, semi-automatic or fully automated. Modutek’s SolidWorks Simulation Professional and Flow Simulation software allows customers to optimize their operation, reliably reproduce cleaning procedures and precisely control cleaning.

Modutek can evaluate the cleaning requirements of semiconductor manufacturing facilities and research labs and provide custom solutions for their specific requirements. The company’s equipment combines the latest technology with the highest quality and reliability. Modutek can provide their expertise and experience and work directly with clients to improve the silicon wafer cleaning processes for their specific application. For a free quote or consultation on call 866-803-1533 or email Modutek@Modutek.com.

Silicon Wafer Cleaning: Effectively Removing Contaminants to Improve Yields

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Silicon Wafer Cleaning: Effectively Removing Contaminants to Improve YieldsSuccessful semiconductor manufacturing relies on the effective cleaning of silicon wafers at several stages of the manufacturing process. Impurities, contaminants and residues from process steps have to be completely removed to ensure that the manufactured components have the required functionality and the desired quality. Silicon wafer cleaning equipment such as those offered by Modutek helps increase yields and improves the cleaning process to deliver high quality results.

RCA Cleaning

Standard RCA cleaning, named after the RCA Corporation where it was developed, involves immersion of the silicon wafers in hot acidic and alkaline solutions. The first bath usually contains hydrogen peroxide and ammonium hydroxide while the second bath has hydrogen peroxide with hydrochloric acid. The first solution removes organic contaminants from the surface of the silicon wafers by dissolving the bonds binding the contaminant particles to the silicon and by the oxidizing action of the chemicals. The second solution dissolves and removes alkaline residues and metallic particles.

RCA cleaning is the most common cleaning method used in the semiconductor manufacturing industry. It is especially effective in removing particles responsible for defects in semiconductors. When detected, such defects reduce the semiconductor yields of the manufacturing process and, if not detected, they reduce the quality of the resulting components.

Megasonic Cleaning

Cavitation bubbles created by the use of megasonic cleaning systems complement the chemical cleaning action of RCA cleaning. As semiconductor geometries become smaller and smaller in size, microscopic particles become more important in the creation of defects. Particles that might be too small to impact the function of large components become critical defect-producing factors for the smallest semiconductor structures.

The bubbles of megasonic cleaning systems add a mechanical component to the overall cleaning action. When the cavitation bubbles burst, they release energy that helps dislodge contaminant particles from the silicon substrate. This mechanical cleaning action can speed up the overall cleaning process and make it more effective in removing even the smallest particles.

SPM Clean – Piranha Etch

When silicon wafers are heavily contaminated, for example when contaminants are clearly visible or for the removal of photo resist after wafer processing, piranha etches provide a powerful cleaning method. The cleaning solution is made up of a mixture of hydrogen peroxide and sulphuric acid. The solution is highly corrosive and yields aggressive cleaning to remove large amounts of material. Sometimes wafers can be run through a piranha etch treatment before further cleaning with the RCA method.

FEOL and BEOL Processing

Front End of Line (FEOL) processing is the part of semiconductor manufacturing in which the components, such as transistors, are created in the semiconductor wafer, while Back End of Line (BEOL) processing involves depositing the metallic interconnections. Cleaning may be required after etching, after ion implantation or after metal deposition to remove process residue.

Water-based cleaning removes some of the impurities and RCA cleaning or piranha cleaning may be used to remove masks, photo resist or chemical residue. Ultrasonic cleaning is effective in helping remove particulate contaminants and ozonated deionized water may be used as well. At the end of each cleaning process, the wafers may be dried with isopropyl alcohol (IPA) in preparation for further processing steps.

Silicon Wafer Cleaning Equipment

Modutek has specialized in silicon wafer cleaning equipment for the semiconductor manufacturing industry and can deliver a complete spectrum of semiconductor cleaning solutions. In addition to chemical cleaning stations, Modutek incorporates the use of Megasonic cleaning equipment and IPA dryers.

Modutek silicon wafer cleaning solutions are based on the company’s thirty years of experience in providing semiconductor manufacturing equipment to the semiconductor industry. Modutek’s team of engineers can advise customers on the choice of equipment and design custom cleaning solutions for a wide variety of applications. If you need reliable and effective silicon wafer cleaning equipment in your manufacturing process, contact Modutek at 866-803-1533 or email sales@modutek.com.

How the Silicon Nitride Etch Process Is Supported By Modutek

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The silicon wet etching process is used in the manufacture of integrated circuits to selectively remove silicon nitride with respect to silicon oxide. Engineers and process specialists in the industry who work with semiconductor equipment manufacturers owe a great deal of their expertise to the quality of the etching equipment at their disposal today.

Background

Integrated circuit fabrication processes include selectively removing silicon nitride using wet or dry etching. Selectivity between materials removed and not removed should be high. However, selectivity is not the only consideration. In a manufacturing environment, a process engineer needs consistent and repeatable results from high-quality and reliable equipment.

Field Oxides Provide Mask Layer

Field oxides deposit a dielectric mask layer over silicon using a patterning mask layer exposing the silicon or oxide, and growing the thick oxide called field oxide. The preferred choice of dielectric for the mask layer is silicon nitride. This process is LOCOS, Localized Oxidation of Silicon. A polysilicon layer is frequently present beneath the nitride. This is a Poly Buffered LOCOS stack. Thus, both silicon nitride and polysilicon must be removed without affecting the silicon oxide.

Aging Effects and High Particle Count

Wet etching techniques are used for stripping nitride and silicon when oxides are present. Silicon nitride is etched in phosphoric acid that is boiling. Amounts of nitric acid may be in the bath. These baths are susceptible to aging and have higher particle counts because the silicate concentration in the bath increases. Others use separate baths for nitride and polysilicon. This increases the number of baths required and can lead to pitting of the pad oxide, which engineers overcome by using a bath with phosphoric, hydrofluoric, and nitric acids. Bath life is extended by hydrofluoric and nitric acids. Nitric acid is required to oxidize silicon. The initial etching selectivity of nitride to oxide may be undesirably low, with selectivities of 9:1 observed, and depends on fluorine concentration. Higher initial etch selectivities are preferred.
Before etching silicon nitride or polysilicon to silicon oxide, you should add silicon to the etch process bath. The silicon enhances initial etch selectivity. Fluorosilicates also can be used. These compounds dissolve readily in phosphoric acid without particles. The compounds increase the etch selectivities to 40:1 and 33:1 for silicon nitride and polysilicon. The additional silicon stabilizes may be in the bath from initial use until its use is terminated. Variations of this procedure are tested and reviewed by engineers and researchers.

Equipment Innovations

IC equipment suppliers provide manufacturers and researchers with leading-edge products required for producing smaller geometry semiconductors, thin-film heads, and MEMS, and also need to offer service, support, and retrofitted systems. These products are usually designed to meet the specific requirements of manufacturers.

Silicon Nitride Etch Baths that Provide Safety, Control, and Flexibility

The Nb Series Operation Process used with Modutek’s silicon nitride etch baths guarantee process control, safety, and flexibility with a two-level diagnostic system monitoring temperature while maintaining an acid-to-water ratio through D.I. water supplementation. By using a new remote metering system, the Nb Series is easy to install and service in new or existing stations. Process engineers know that this kind of equipment needs to be manufactured and supported by a company that:

  • Has extensive experience and expertise;
  • Uses the latest technology;
  • Meets specific customer requirements;
  • Provides high-quality and reliable equipment;
  • Offers excellent technical support and onsite repairs

Modutek has over 30 years of experience providing high-quality and reliable equipment to support the silicon nitride etch process and is a leader among semiconductor equipment manufacturers. If you need to discuss your process requirements or would like a free quote, call Modutek at 866-803-1533 or visit www.modutek.com.

Tips on Buying Silicon Wafer Cleaning Equipment

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Tips on Buying Silicon Wafer Cleaning EquipmentFor all manufacturing involving semiconductors and micro electrical mechanical systems (MEMs), one of the most important requirements is to maintain a precise cleaning process of silicon. This reduces yield problems that occur from both the organic and inorganic residues. As the size geometry and size of semiconductors continue to become smaller, there are higher risks associated with contamination of wafers especially by particle contaminators. For increased efficiency in your manufacturing processes you will need to purchase high quality and reliable silicon wafer cleaning equipment for your manufacturing facility.

Here are 5 factors to consider when shopping for silicon wafer cleaning equipment:

  • Buy from a company with experience and expertise

Silicon wafer cleaners are different from other products you will buy on the market and fit into manufacturing environment.  When you are purchasing this equipment you will need to look for a company that has a proven track record with in-house expertise and support. You also need to confirm that the equipment they provide will meet all of your manufacturing requirements.   Upcoming companies with little experience are likely to sell you substandard products or products that are not fully qualified to meet your requirements. Companies that have been in the field for a long time will offer various equipment options based on their experience working with various customers.

  • Buy equipment manufactured using the latest technology

As the quality and geometry of the MEMs and semiconductors advance, the technology used to make wafer cleaners have also advanced. Finer geometries require finely washed and cleaned silicon unlike in previous years which involved just simple immersions in hot alkaline. The modern cleaning equipment uses megasonic cleaning, centrifugal spraying, and ultrasonic cleaning technologies. The enclosed systems effectively clean all particles and contaminant films. You’re better off buying from a company that implements such advanced technology.

Photoresists require sophisticated cleaning methods like the piranha cleaning process which uses a mixture of sulfuric acid and hydrogen peroxide to clean organic residues off substrates. This process requires that the equipment and procedure used be carefully followed to insure safety.

  • Confirm that the equipment supports user manufacturing requirements

Cleaning equipment will always feature different cleaning aspects. You should check the manufacturer’s specifications to ensure that they match your requirements to ensure optimization of the resource. Wafer cleaners with additional features may be unnecessarily expensive if you never use some of the features.

  • High quality and reliable tools

Money will always be a factor when it comes to purchasing wafer cleaning equipment, but quality and reliability must never be compromised. High quality and reliable equipment will last longer, work better and will not compromise the reputation of the manufacturer.

  • Buy from a company that offers technical support and onsite repair

Many companies will sell you a product, but will not always offer good technical support and onsite repair if there is a problem. If a manufacturer does not offer good technical support or if the system does not work reliably, your manufacturing yields will be compromised. It is advisable to buy from a company that will offer technical support and repair of their wafer cleaning equipment in case of breakdown or malfunction.

Summary

With these factors in mind, work with a manufacturing supplier that provides reasonably priced yet effective silicon wafer cleaning equipment that is both efficient and durable. At Modutek Corporation, we strive to do this for all our customers and have been providing the high quality of equipment, service and support for over 30 years. Call us for a free quote at 866-803-1533 or visit our site at www.modutek.com.

Silicon Wet Etching Using Modutek’s Nitrite Etch Bath

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Silicon Wet Etching Using Modutek’s Nitrite Etch Bath

Silicon Wet Etching Using Modutek’s Nitrite Etch Bath

Modutek has been designing and manufacturing Silicon Wet Etching components and related equipment for over 30 years. Their more recent Nitrite Etch Bath products, including the “Nb” series, are an upgrade to their “Na” series. The Silicon Nitride Etch Bath has been designed and engineered to provide unparalleled process control. You can also expect flexibility and safety as key components of these systems.

Part of what makes the Nb Series silicon nitride etch bath stand out is its two-tiered diagnostic system. This allows the user of the system to monitor the temperature at the same time as it maintains the acid-to-water ratio through supplemented D.I. water. This new metering system makes the Nb easier to install. It also allows for service in existing process stations or in new ones.

Some of the benefits of the Silicon Wet Etching system include, but are not limited to, the following:

  • Controlled Nitride Etching
  • Nitride Etch Uniformity
  • Remote DI water metering system
  • Controls chemicals boiling (no “bumping”)

The silicon nitride etches function in a combination fluid – 85% phosphoric acid (H3PO4) and 15% DI water. These fluids boil at 160°C. Since the water will boil off some of the solution as steam, the NbSeries silicon nitride etch bath includes a refluxor which cools the condenser to cause the steam to condensate back to water which maintains the solution. Please be aware, the condensers are not 100% efficient, which will make it necessary to add water to the solution periodically.

Generally, it is discouraged to add water to acid, but it is required in this case. We have determined some safe ways to do this. For instance, if the acid rapidly agitates or boils, you can add a small amount of water which mixes right away. This poses no safety issues. When the water is added to non-boiling acid, the water sits on top of the acid. More water is added to the top layer of the acid. The water will mix as the heat absorbed by the water makes it boil. The water mixes thoroughly with the acid and the correct reaction occurs.

A basic chemistry rules states, “The temperature of a solution cannot rise above its boiling point, except under special circumstances.” The heater on our system does not have to be controlled the way it is required on other systems. If the heater switch is on, the heater is on. By choosing not to regulate the heater, the heat solution is allowed to boil regardless of the concentration. The system keeps it boiling while water is added to adjust the concentration, which remains at the upper set point.

The Silicon Wet Etching and Nitrite Etch Bath systems also include the following features:

  • Etched-foil resistance heater
  • PVDF or Teflon reflluxor with safety cover
  • Vapor thermocouple
  • Uniformity heat transfer
  • Ease of installation and repair for new or existing wet station configurations

System Specifications include the following:

  • Application: Silicon Nitride Etch
  • Operating temperature range: 30 – 180º C
  • Chemical usage: H20, H3PO4
  • Heat-up rate: 2-3 º C per minute (rate affected by size of system)
  • Process temperature control: ± 0.5º C
  • Vapor thermocouple for chemical boiling control
  • PVDF refluxor with Teflon® cooling coils
  • One year warranty

Companies that need additional features may consider any of the following options. Modutek will work with you to design the Silicon Wet Etching system that best meets your company’s needs. Options include, but are not limited to:

  • Teflon® gravity drain system
  • Auto cover which is pneumatically actuated
  • Remote operation timer switches
  • Aspirator valve system
  • Model C1815a process controller/timer
  • RS232 Interface

To learn more about the Silicon Wet Etching products sold by Modutek Corporation, or to learn how our products can be redesigned to work with your Nitride Etch Baths or Quartz Baths and Sub Ambient Systems (BOE), contact us at 866-803-1533.

Advanced Ozone Cleaning Process for Photoresist Strip, Etch and Clean

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Advanced Ozone Cleaning Process for Photoresist Strip, Etch and CleanAs a company, are you spending too much money on chemicals and chemical disposal costs? You can save money by using Modutek’s Advanced Ozone Cleaning Process equipment. Modutek will work closely with you to design and manufacture the best possible ozone cleaning process for your application.

Take time to research and discover the advantages of our ozone cleaning process. Awarded with a Green Technology certificate, we can substantially reduce your process chemical dependencies. Our ozone cleaning process can strip, clean or etch your wafers, substrates and solar devices for less than half the cost of conventional technology.

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