Advanced Wafer Drying using Modutek’s IPA Vapor Dryer

Advanced Wafer Drying using Modutek's IPA Vapor DryerThe successful manufacture of tightly packed semiconductor products depends on obtaining low particle counts on silicon wafer surfaces after rinsing. Heat drying and spin dryers may leave water marks and residue as the water evaporates. Modutek’s advanced IPA vapor dryers use the Marangoni drying effect to reduce particle counts to a minimum. The compact dryer unit can be integrated into wet processing equipment as needed. Modutek’s IPA vapor dryers can increase yields and improve output quality based on reduced particle counts compared to other drying methods.

How the IPA Vapor Dryer Works

In Modutek’s IPA Vapor dryer, an even vapor distribution is ensured by introducing the IPA vapor at the top of the dryer. The vapor is generated in a standard one-gallon bottle located in the exhaust compartment and fitted with a level sensor. Changing the bottle is quick and easy. This arrangement reduces IPA consumption but allows enough vapor to develop the surface tension gradient. As water drains from the bath and runs off the silicon wafer, a small amount of IPA vapor interacts with the thin film of water still coating the wafer. Because IPA has a lower surface tension than water, the surface tension gradient causes the water to flow off the wafer surface. As the water retreats, its flow takes along contaminating particles and other impurities, leaving the wafer completely clean. Because no water is left on the wafer surface, water marks from evaporating water are eliminated.

Advanced Wafer Drying Delivers Many Advantages

The main advantage of using Modutek’s IPA vapor dryer is the reduced particle count. Spin dryers can add particles from the centrifugal action of the spinning. Also, some water will be left to dry, leaving water marks. The Marangoni drying effect utilized in the IPA Vapor Dryer significantly improves wafer cleanliness. Other advantages of Modutek’s dryer include compact installation, low IPA use, and a simple design with no moving parts. The dryer design is flexible enough so that it can be integrated into wet processing equipment. The dryer function can use the same tank as rinsing to save space with a single cabinet. Since the wafers don’t spin, there is no risk of breakage, and a typical drying cycle is completed in ten to fifteen minutes.

The Use of Modutek’s IPA Dryer Can Provide Substantial Benefits

A semiconductor manufacturer can reap substantial benefits when Modutek’s IPA vapor dryer is integrated into wet processing equipment. These include the following:

  • Higher throughput due to faster drying times
  • Higher yields due to fewer defects from contaminating particles
  • Lower costs because of low IPA consumption
  • Reduced space due to compact cabinet construction and integration with rinsing
  • No IPA heating required
  • Flexibility due to multiple drying recipes
  • Easy operation with PLC and touchscreen
  • Safe operation with safety interlocks, auto lid, and PVC side shields
  • Interface capable of working with robotics in wet bench
  • No breakage from spinning because there are no moving parts

Additional Features for Specific Applications

In addition to the direct benefits listed above, Modutek’s dryer can be adapted to specific wet process applications. Possible options include an ozone feature that introduces ozone into the cabinet, a quick dump feature, a static eliminator, data logging, and fire suppression. The dryer can handle all wafer sizes and most glass substrates.

Modutek Provides Solutions to Meet Customer Needs  

Modutek understands wet-process semiconductor manufacturing and has the in-house expertise to find the best solutions. When working with customers, Modutek can evaluate customer needs and make specific proposals from their complete line of wet-processing equipment. After delivery and installation, Modutek provides unparalleled support to ensure the equipment continues to meet customer expectations.

Free Standing IPA Vapor Dryer Improves Wafer Processing

When a series of semiconductor manufacturing steps are complete, the silicon wafers have to be rinsed and dried. At this stage in the fabrication process, the surface of the silicon wafer has to be as free as possible from particle contamination wafer and free from water marks caused by the water evaporating on the wafer. The free-standing IPA vapor dryer uses IPA (isopropyl alcohol) to eliminate water marks and reduce the particle count. IPA vapor drying, also known as Marangoni drying, delivers clean wafers for improved processing by increasing yield and output quality.

IPA Vapor Drying Works by Removing Water from the Wafer Surface

In IPA vapor drying, the silicon wafers are first rinsed with deionized water. IPA vapor is then introduced into the closed drying chamber. Where the IPA interfaces with the deionized water on the wafer surface, the lower surface tension of the IPA causes the water to flow off the wafer surface, taking impurities with it and leaving the wafer clean and dry.

This method of drying silicon wafers is a good alternative to spin drying because it does not stress the wafers mechanically and leaves no water marks. Rinsing and drying takes place in a single unit, avoiding a transfer of the wafers and eliminating a source of contamination. The IPA drying method can be cost-effective, especially if the consumption of IPA is kept low. IPA drying gives excellent results in terms of low particle counts and wafer cleanliness.

Modutek’s IPA Vapor Dryer Provides Superior Performance with Low Operating Costs

Modutek’s free-standing IPA vapor dryer is made from polypropylene with Teflon fittings and pipes. Its 30-inch wide space-saving design can easily be integrated into a wet processing equipment production line or used independently to rinse and dry wafers. The IPA vapor is introduced at the top of the enclosure from a standard one-gallon bottle located at deck level in the exhaust compartment for easy bottle changes. From the top, the vapor is distributed evenly throughout the chamber. Drying time is typically about ten to fifteen minutes.

In addition to the basic drying function, Modutek’s design also includes de-ionized water degassing, N2 head case purging, and hot N2 drying. The station is operated from a touch screen with an intuitive graphic user interface that allows the programming of multiple operating sequences.

Features include a continuous flow deionized water manifold, an automatic lid that opens with a foot switch, and removable PVC side shields. Options include a manual lid, a quick dump feature, data logging, and the use of ozone to eliminate remaining organic impurities. For special applications, Modutek can adapt the dryer design to meet customer requirements.

Advantages and Benefits of the Free Standing IPA Vapor Dryer

With vapor generation inside the standard bottle and vapor introduction from the top of the enclosure, Modutek’s IPA vapor dryer has a very low IPA consumption and low operating costs. The included features and options along with possible customization allow for flexible operation and make the dryer an ideal addition to a semiconductor fabrication line. Excellent rinsing and drying performance, rapid operation, and programmable cycles deliver superior results and higher throughput. Clean wafers with low particle counts can reduce rejects and improve yield. The flexible design makes the station suitable for production lines, batch processing, and individual prototyping or test products.

Based on the company’s extensive experience in the design and building of semiconductor manufacturing equipment, Modutek can advise customers on the type of system they need and can deliver equipment from its complete line of wet process stations. Modutek designs and builds all its own products in-house and has the expertise to ensure IPA vapor dryers and other equipment meets the needs of customers and performs as required. Contact Modutek for a free quote or consultation to discuss your specific requirements.

How the IPA Vapor Dryer Further Improves Wafer Processing

The Advantages of Using Modutek's Quartz Tube Cleaning StationsWhen silicon wafers are dried after rinsing, the wafer surface has to be free of water marks and contaminating particles. This is especially true after hydrofluoric acid removes the silicon oxide layer during the last etching before further processing. The wafers are subsequently exposed to diffusion or vapor deposition and surface contamination will result in defective components.

During the IPA vapor dryer process, water flows off the surfaces of the wafers without evaporating and leaving water marks. Particle contamination is minimized and the wafers remain clean. The Modutek IPA vapor dryer is a space-saving way of ensuring high-quality semiconductor output for wet process manufacturing facilities and research labs.

Modutek’s IPA Vapor Dryer Delivers Clean Wafers While Reducing Costs

Modutek’s IPA vapor dryer incorporates rinsing and drying in a single station to reduce costs, save space, and minimize the handling of the silicon wafers. The station first rinses the wafers with de-ionized water and then introduces IPA vapor into the drying cabinet. The vapor is generated in a one-gallon bottle situated in the exhaust compartment for easy changing.

The IPA vapor is introduced into the drying chamber from the top to ensure even distribution, reducing the amount of IPA required and further reducing costs. When the IPA vapor condenses on the wafers, a surface tension gradient develops between the IPA and the remaining water. The water flows off the wafer surfaces, taking contaminating particles with it. The dry wafer surface doesn’t have any water marks and is practically particle-free.

Advantages and Benefits of Modutek’s IPA Dryer

Modutek’s IPA dryer lets operators transfer the silicon wafers from the last etch processing station to the dryer chamber without any further movement of the wafers. Wafers are fragile and can easily pick up particles when moved. With the single rinsing and drying chamber, wafers avoid damage and remain as particle-free as possible.

The IPA drying method is a gentler alternative to heat drying or rotating the wafers to spin off excess water. Heating leaves particles in place and thin wafers can break when spun rapidly. Instead, the IPA dryer has no moving parts, eliminating sources of potential damage to the wafers. A drying cycle typically takes around 15 minutes.

IPA dryer cabinets are a compact 30 inches wide and made of white polypropylene. The graphic user interface operates via a touch screen and features multiple recipes. The SolidWorks Simulation Professional and SolidWorks Flow Simulation software calculates process flow characteristics and often reduces the required drying time. The Modutek IPA vapor dryer is a customizable unit that can be designed to fit into customer wet process lines and meet customer requirements.

Modutek Designs and Builds Their IPA Dryer Systems in House

Modutek’s IPA dryer is designed, built and tested at the company’s San Jose, California facility. Modutek does not outsource any of this work and even develops its own software, the SolidWorks Simulation Professional and SolidWorks Flow Simulation programs. As a result, Modutek can offer highly customized versions of its IPA dryer. Modutek engineers can work with customers to integrate the IPA vapor dryer in an existing wet process line or design a custom free-standing unit to meet the requirements of the customer application.

With more than 40 years of experience in wet process semiconductor manufacturing equipment, Modutek can analyze the needs of its customers with a free consultation. The company can then recommend equipment from its complete wet process equipment line and from associated equipment such as tanks, chemical handling equipment and lift stations. In each case, Modutek can offer customized systems and equipment to meet the needs of its customers.

Achieving Optimum Particle Removal in a Wet Bench Process

Achieving Optimum Particle Removal in a Wet Bench ProcessAs component packing is tighter and circuit geometries trend towards smaller structures, the reduction of submicron particle contamination during the wet bench process steps becomes more important for output quality. When circuit paths are reduced in size, a single submicron particle can block the path and render the final semiconductor component defective. Even when the presence of particles doesn’t cause defects, their influence on semiconductor performance can reduce the quality and lifespan of the final products.

Semiconductor manufacturing facilities and research labs using typical wet bench equipment face challenges when trying to reduce submicron particle contamination to acceptable levels. Innovative solutions such as the use of Megasonic Cleaning and the reduction of wafer handling with a single chamber IPA dryer can help bring down the particle count. When such solutions are integrated directly into the wet bench processing line, throughput and yields can increase. The process may require fewer chemicals and overall facility performance can improve.

How Megasonic Cleaning Reduces Particle Contamination

The use of high-frequency sound waves in cleaning systems is common in many industries but the delicate silicon wafer structures and surfaces require extra-high frequencies to make sure wafers are not damaged. Megasonic cleaners use frequencies of 950 kHz and higher, in the megahertz range, to deliver the soft cleaning action required.

The sound waves from lower frequency systems create microscopic but comparatively large cavitation bubbles in the cleaning bath. The bubbles produce intense scrubbing against the surfaces of the parts to be cleaned, dislodging contaminants and delivering a powerful cleaning action. For the soft surfaces, delicate structures and thin metallic deposits of silicon wafers, such intense cleaning can result in the pitting of surfaces and damage to silicon structures.

In Megasonic cleaning systems, the high-frequency sound waves produce smaller bubbles and more gentle scrubbing. The cleaning action is soft enough to preserve silicon surfaces and structures but strong enough to dislodge contaminating particles. The particles often adhere to the wafer surfaces and are difficult to dislodge with normal rinsing. Megasonic Cleaning breaks the adhesion and creates currents that wash the particles away.

The Megasonic Cleaning action is especially important for submicron particles where the adhesion to the wafer surface inside a boundary layer makes rinsing less effective. The soft scrubbing of tiny bubbles against the wafer dislodges submicron particles effectively and reduces particle contamination.

How the Single Chamber IPA Dryer Reduces Particle Contamination

One of the ways silicon wafers pick up contaminating particles is during the transfer from etching to drying stations. This transfer is especially critical for HF last etching. During the final etching in a wafer fabrication step, the silicon oxide layer is removed through etching with hydrofluoric acid. The wafer is then rinsed and dried before moving on to the next fabrication step. Particles remaining on the wafer surface can interfere with the subsequent fabrication process.

In an innovative development that eliminates this source of particle contamination, a single chamber handles HF last etching and IPA vapor drying. First, hydrofluoric acid is injected into the station chamber to etch the wafer. When etching is complete, the wafer is rinsed with de-ionized water until the acid is neutralized to a safe pH. IPA vapor is then introduced into the station chamber, and after about 15 minutes, the wafers are dry and ready for the next fabrication step. The particle count remains low because the wafers have not been moved throughout the etching and drying process.

Modutek Provides Innovative Semiconductor Manufacturing Equipment for Excellent Results

Modutek works closely with customers to develop innovative wet bench stations that meet their requirements. Attention to customer needs and finding new solutions to common problems allow the company to remain one of the leading wet bench manufacturers.

For Megasonic Cleaning applications, Modutek has partnered with Kaijo Corporation, a world leader in high sound frequency cleaning technology. Modutek’s integration of the Kaijo Megasonic cleaners into the wet bench product line has produced low particle counts that are difficult to obtain with other methods.

Because Modutek designs and builds its own etching and IPA drying stations in house, the company was able to develop its innovative single chamber station and integrate it into its comprehensive wet process product line. In parallel with Megasonic Cleaning, the single chamber station further reduces particle counts, improves yields and reduces costs. On these and other wet process questions, Modutek offers free consultations to ensure customers get the best equipment for their needs.

How the IPA Vapor Dryer Provides Superior Wafer Processing

After etching and rinsing, an IPA (isopropyl alcohol) vapor dryer can produce dry silicon wafers without watermarks and limited particle adders. In IPA drying, also known as Marangoni drying, the Marangoni effect relies on the low surface tension of IPA compared to water. When IPA vapor is introduced into the drying chamber, a surface tension gradient is established between the IPA and water on the surfaces of the silicon wafers. The surface tension gradient causes the water to flow off the wafers, leaving them clean and dry. The slow drain water feature also helps reduce particles contaminating the wafer surfaces. As a result, IPA vapor drying can be used to produce especially clean, wafers after a final etch and before the next semiconductor manufacturing step.

IPA Vapor Drying is Safe for Thin Silicon Wafers

IPA vapor dryers are especially suitable for drying thin, delicate silicon wafers. In other drying methods, the wafers are placed in a drying chamber and rotated or spun to remove the rinsing water, but handling and moving these wafers can result in damage. With the IPA vapor dryers, the Marangoni effect dries the wafers without moving them. Delicate wafers are not subjected to any stress and damage is minimized while drying performance is excellent.

IPA Vapor Dryers Improve Wafer Processing After HF Last Etching

As the final process in a silicon wafer fabrication step, the silicon oxide layer on the wafer has to be removed with hydrofluoric acid (HF) etching. The wafer is then rinsed with de-ionized water and dried before passing on to the next step in manufacturing the final semiconductor component. Providing a clean wafer with a low particle count is critical at this point because subsequent process steps are affected by the presence of contamination or particles. For high-density semiconductor components, a particle or film on the silicon wafer can prevent the correct etching of a structure or the deposit of a conductor. Because IPA vapor dryers remove water from the wafer surface and reduce particle counts with their Marangoni effect, IPA vapor dryers improve wafer processing results and ensure higher quality output.

Modutek Single Chamber Processing Delivers Further Improvements

At the end of a wet process wafer fabrication step, the wafers are etched with hydrofluoric acid in an etching chamber and then transferred to a dryer. The transfer exposes the wafers to particle contamination that can lead to elevated wafer surface particle counts, even after Marangoni drying. Modutek has eliminated this source of contamination by developing a method that allows etching and drying in a single chamber.

With the Modutek etching and drying station, hydrofluoric acid is injected into the chamber at a controlled ratio to etch the oxide layer down to the bare silicon. The wafers are then rinsed with de-ionized water to a set pH level. When the pH level is reached rinsing is complete and drying can begin.

IPA vapor is generated from a standard one-gallon bottle and introduced at the top of the drying chamber. The drying cycle takes about 10 to 15 minutes and the dry wafers are ready for their next fabrication step. The wafers are not moved during the whole etching, rinsing and drying process, reducing wafer breakage, especially for thin, delicate wafers. Since the wafers stay in the chamber from etching to drying, particle contamination is significantly reduced.

Modutek’s extensive experience in the semiconductor manufacturing industry allows it to support customers in integrating the new single chamber IPA vapor dryer in any new or existing wet processing equipment. Modutek designs and builds their own semiconductor manufacturing equipment and can therefore offer customized versions to meet the requirements of any application. The company’s staff work with a customer’s engineering team to make sure the equipment meets the customer’s process requirements. Contact Modutek for a free quote or consultation to discuss your manufacturing equipment requirements.

How the IPA Vapor Dryer Improves Wafer Processing Results

how-the-ipa-vapor-dryer-improves-wafer-processing-results

Not every advancement in semiconductor fabrication produces results that are usable in industry. To be of value, advancements need to be consistently repeatable when used on an industrial scale. Modutek’s IPA vapor dryer falls into this category, helping semiconductor fabricators improve both yields and processing times.

Modutek’s IPA vapor dryers are custom-engineered with in-house experts working in partnership with a client’s technical staff. From a thorough understanding of a client’s manufacturing process, Modutek works to make sure their equipment is designed and tested to meet the requirements.

The Marangoni IPA Vapor Dryer Design

Silicon wafers require cleaning, rinsing and drying at certain stages of the fabrication process. The results need to be as close to perfection as possible, with no watermarks, and minimal particle contamination. In the past, these results were obtained through rapid spinning and heat drying. These simple methods no longer work with the latest high-density wafers, however. Not only is water hard to remove from complex shapes, drying without leaving watermarks is impossible.

Contamination from incorrect cleaning and drying can cause serious product malfunction and high failure rates. This is where drying by isopropyl alcohol comes into play. IPA drying by the vapor method, delivers wafers that are completely free of watermarks and with minimal contamination. Modutek’s IPA vapor drying system is both cost-effective, and ready for seamless integration into the standard wet bench process or free-standing design.

How the IPA Vapor Dryer Design Works

Modutek’s IPA vapor dryer design is unique in a number of ways. This design delivers high-quality results through serving IPA vapor at the upper reaches of the drying tank. This makes sure that vapor distribution is even. Since the surface tension of isopropyl alcohol is lower than that of water, such vapor serving introduces a gradient of surface tension where isopropyl alcohol meets with a layer of water on the wafer surface. With this type of drying effect, water quickly leaves the wafer surface, and leaves it completely dry and clean. Since the water does not actually evaporate, it leaves the watermarks behind. The drying process takes no longer than 15 minutes.

The Advantages of Modutek’s IPA Vapor Dryer

Modutek’s in house experts in IPA vapor dryer design work together with a clients’ technical team to design and create IPA dryers that specifically meet their application requirements. Clients are able to come to Modutek’s facility for testing to make sure that their equipment works as expected.

With extensive experience in the wafer processing industry, Modutek is fully able to provide top-notch equipment and customer support at every stage of the design process, during delivery and after the sale. With expertise in semiconductor processing equipment, Modutek is able to address every specific client need for this industry. Contact Modutek for free consultation on the equipment needed for your specific wafer manufacturing process.

 

 

 

Modutek at 2018 Semicon Conference in China

2018 Semicon Conference ChinaModutek Corporation, a leading provider of wet bench stations and wet process equipment, will be at the Semicon Conference in Shanghai China from March 14-16, 2018 with their factory representative Laserwort Ltd.  They will be located in Hall N2 at booth 2431. Information about the Semicon Conference can be referenced at http://www.semiconchina.org/ and details on Modutek’s attendance at the conference can be referenced at: Modutek at Semicon Conference in China

Come by the Modutek /Laserwort booth to get information and answer any questions you have about using Wet Bench Process Stations for acid/base, solvent and ozone cleaning or photo resist strip.  In addition Modutek will also provide information about the benefits of their new IPA vapor dryer with the HF last process. Modutek serves customers around the world who require any type of wet processing equipment and builds chemical delivery systems for pharmaceutical, biochemical, solar and semiconductor manufacturing.

Additional details on some of Modutek’s products are listed below:

Single Chamber HF Last IPA Vapor Dryer

Benefits include:

  • Most drying cycles completed within 10 to 15 minutes
  • Very low consumption of IPA
  • No moving parts inside drying chamber eliminating wafer breakage
  • Eliminates watermarks
  • Drying technology can be designed into wet bench eliminating one transfer step

Features include:

  • Single drying chamber for DI water rinsing and IPA vapor drying
  • On board HF metering for precision mix ratios
  • Uses an in situ HF etch process with a rinse step before the IPA drying cycle
  • Filter bypass for contamination control with no cassette contact points
  • Easy to change IPA bottles
  • Handles all process sizes (standard wafer carriers to glass substrates)

 

Fully-automated Wet Bench Equipment

Benefits include:

  • In house customization to meet customer process requirements
  • Precise automated process execution and reliable repeatability
  • Full automation control with touch screen
  • Improved yield and reduced errors
  • SolidWorks Simulation software for accurate calculation of process parameters
  • All robotics and software design designed in house
  • Complete design, assembly and test at one location to meet your specifications

 

Semi-automated Wet Bench Equipment:

Benefits Include:

  • Automation control with touch screen
  • Servo motor automation
  • SolidWorks Flow Simulation software
  • SolidWorks Simulation Professional software
  • All robotics and software designed and developed in house
  • Complete design, assembly and test at one location to meet your specifications

 

Manual Wet Bench Equipment:

Benefits Include:

  • High end manual equipment at competitive pricing
  • Meets or exceeds all current safety standards
  • Low cost of ownership
  • Designed to meet any process requirements
  • Can accommodate custom designs and processes
  • Equipment designed for future expansion

 

All wet bench equipment supports the following applications:

  • KOH Etching
  • Quartz cleaning
  • Ozone Strip
  • Ozone Cleaning
  • SC1 & SC2 (RCA Clean)
  • Megasonic Cleaning
  • BOE (Buffered Oxide Etching)
  • MEMs processing
  • All solvent applications
  • Hot phosphoric (Nitride Etching)
  • SPM Cleaning
  • Precision Part Cleaning

Modutek has over 37 years of industry experience and expertise in developing and building wet bench stations and wet process equipment that provides highly reliable results for precision processes. They also provide world-class service, and customer support. Contact Modutek at 866-803-1533 or email [email protected] for a free quote or consultation to discuss your requirements.

 

Advantages of HF-Last Etching and IPA Drying in One Chamber

In the final stage of silicon wafer cleaning the silicon oxide layer has to be removed and the clean wafer dried without contamination. When wafers are removed from the HF etching process and transferred to a drying chamber, the extra handling increases the chances for wafers to pick up contaminating particles. Such particles cause errors in the further processing of the wafers and can result in final semiconductor products that are defective or of poor quality. Carrying out the final etching and the wafer drying in one chamber reduces the possibility of contamination and can result in better output quality. The latest field results from a customer using Modutek’s single chamber HF-last and IPA vapor dryer show a substantial reduction in particle counts on wafer substrates.

The Single Chamber Process

Modutek uses IPA vapor (Marangoni) drying in a free-standing unit with one drying chamber for DI water rinsing and drying. The IPA vapor is generated in a standard one gallon bottle and is introduced into the drying chamber through the top cover to ensure even distribution. IPA consumption is low but is still adequate to give surface tension drying across all wafers and substrates. The Marangoni drying technique results in wafers without any watermarks.

To allow single step etching and drying in one chamber, Modutek modified the IPA vapor dryer to include HF (hydrofluoric) acid injection before the start of the standard IPA vapor drying process. The HF acid injection is ratio controlled and provides an oxide etch down to bare silicon. Once etched, the wafers are rinsed to a controlled pH level. When the required pH level is reached, the IPA drying process begins without moving the wafers. The particle count on the wafers remains low.

Field Results

Modutek has supplied the new single chamber HF-last IPA dryer to customers and the first large scale results are now in. In the 0.3 to 5 micron range, fewer than 20 particles (adders) were added to the etched substrate after using the Modutek etching/drying combined system. These particle counts are substantially below those achieved using the previous process in this particular field trial. Semiconductor manufacturing facility managers and research center engineers can compare these results to particle counts resulting from their current process and may be able to achieve significant improvements using the Modutek equipment.

The number of microscopic particles on wafers is becoming more and more critical as micro-structures and electronic features become smaller. Where comparatively large conducting areas and physical structures can work well even when they contain a disruptive particle, particles in the way of smaller structures either result in defective semiconductor components or in components whose characteristics are not as specified.

Modutek’s single chamber technology lets semiconductor manufacturing facilities improve output performance and increase yield. The entire etching, rinsing and drying process took only about 15 to 20 minutes in this application. One customer is reviewing particle counts, yields and output quality throughout the entire operation because it is likely that the improved facility performance with the Modutek system can justify the cost of acquiring the new equipment.

How Modutek Can Help

Modutek has over 35 years of experience providing wet processing equipment to the semiconductor manufacturing industry. The company has the expertise to advise customers regarding their semiconductor processing needs and can customize their equipment to fit particular applications. Their state-of-the-art equipment has helped wet process facilities meet their production goals in the past and the new single chamber HF-last etch and IPA vapor dryer can now help customers improve overall production line performance and increase facility profitability.

 

How Marangoni Drying Produces Superior Surface Conditioning for Wafer Processing

How Marangoni Drying Produces Superior Surface Conditioning for Wafer ProcessingAt the end of a particular step in silicon wafer processing, wafers often have to be cleaned, rinsed and dried. The resulting wafer surfaces must be free of water, watermarks, particles and organic residues. Older technologies such as spinning the wafers rapidly or heat drying can no longer fulfill the requirements of high density electronic devices on today’s silicon wafers. Water is hard to remove completely from complicated geometries and drying can leave contaminating watermarks and particles.

Such contamination can lead to product defects in subsequent processing steps or to high failure rates as the contamination impacts quality. IPA (isopropyl alcohol) drying using the Marangoni drying effect leads to dry silicon wafer surfaces without watermarks or particles. Modutek’s IPA vapor dryer is cost effective and can be integrated in a wet bench process without adding drying transfer steps.

How it Works

In Modutek’ IPA drying process, IPA vapor is introduced at the top of the drying tank to ensure even vapor distribution. Because the IPA has a lower surface tension than water, it introduces a surface tension gradient where it interfaces with the water on the wafer surface. As a result of the Marangoni drying effect, water flows off the surface of the silicon wafer and leaves it dry and clean.

The departing water also takes along any impurities or particles suspended within it. No watermarks are present because the water does not dry on the wafer surface and ozone can be introduced into the drying tank to eliminate trace organic contamination. There are no moving parts inside the chamber so physical wafer damage is eliminated and drying cycles typically last ten to fifteen minutes.

Modutek’s Design

The stand-alone Modutek IPA dryer is a 30″ wide cabinet of polypropylene construction. It features wiring to NFPA 70 & 79 and has all Teflon fitting, valves and tubes. A touch screen controls operation with a graphic user interface and the dryer has a multiple recipe function.

The unit has an N2 head case purge with an interlock, a hot N2 dry feature, a continuous flow DI water manifold and an auto lid with foot switch open. PVC side shields are removable and there is DI water degassing function using a membrane contactor. Third party certification for NEC and NFPA is available.

Dryer options include PVC construction, a manual lid and a quick dump feature. Data logging and online support are available. Other options include a static eliminator, resistivity monitoring, HEPA fan filter units and a fire suppression system. Modutek can customize any dryer to customer specifications.

IPA Dryer Operation

The Modutek MVD series IPA dryer is a competitive solution with a single drying chamber for DI water rinsing and IPA vapor drying. The IPA vapor is generated in a one gallon bottle installed at deck level for easy changing. Introducing the vapor at the top of the tank is an efficient way of achieving even distribution of the vapor and reduces IPA consumption. The dryer can handle all wafer sizes and glass substrates and Modutek can integrate the IPA drying function into wet bench stations to eliminate a transfer step.

Benefits of Modutek’s IPA Vapor Dryer

Modutek’s specialists work with customer engineering teams to design a dryer that best matches the process application. Modutek’s design and software implementations are all carried out in house and acceptance testing with de-ionized water is available. The company’s extensive experience in the semiconductor manufacturing industry lets it provide first class customer support at all stages of a contract and after delivery. If you need to improve your wafer processing quality and want a free consultation or quote on using an IPA Vapor Dryer, call Modutek or email [email protected].

Tips on Selecting the Right Options for Your Wet Bench Equipment

Tips on Selecting the Right Options for Your Wet Bench EquipmentModutek wet benches are of white polypropylene construction with 304 stainless steel construction available for solvent applications. The company will build any size and length to meet customer requirements. Safety features include safety interlocks, PVC safety shields, emergency power off mushroom buttons and wiring to NFPA 70 and 79. All models have a Teflon N2 gun, a deionized water hand spray and a continuous flow deionized water manifold.

Fully Automated Stations

Modutek’s fully automated wet bench stations use SolidWorks Simulation Professional and SolidWorks Flow Simulation software to optimize the semiconductor fabrication processes and improve performance. The cost of the units covers the basic station and robotics to handle automated operation. These wet process stations are suitable for customers who need high yields, improved etch rates, better throughput and who want the highest output quality.

In addition to increased performance, fully automated stations eliminate human operator error in calculating the chemical dosage and operating the station. The automated system tracks chemical usage to reduce waste and maintain a consistent process environment. Once programmed, the automated station runs the same software and the process is fully repeatable.

Semi-Automated Stations

The semi-automated stations give customers the advanced features and precision of fully automated stations without having to pay the fully automated price. Stations have a graphic user interface on a PCL touch screen to control servomotors with three degrees of freedom and with encoder feedback. Customers can get process uniformity and accurate handling while saving money.

Modutek semi-automated stations are an excellent option for customers who want the precision of robotic controls without paying for full automation. The semi-automated stations still use the SolidWorks Professional and Flow software packages to ensure customers achieve excellent results while spending less.

Manual Stations

Manual wet benches are a cost effective way for customers to get the safety features and operating characteristics of the Modutek wet process equipment family with competitive pricing and an overall low cost of ownership. The manual stations are an effective way for customers to start using wet process equipment and they can later expand the units to add automation options. The manual equipment is of the same quality as the automated stations and delivers excellent performance without the cost of robotics.

Solvent Stations

For solvent stations Modutek uses a 304 stainless steel construction with fire suppression. Solvent stations are available with the same fully automated, semi-automated or manual options as the other wet processing stations and they share the same advanced features. Solvent stations are for customers who have applications with acetone or IPA or who want to carry out photo resist stripping or EDP etching.

Dry to Dry Wet Process Equipment

Modutek’s Dry to Dry equipment saves time by eliminating transfers and increases throughput and yield. It uses an IPA dryer to avoid having to dry in a separate tool. The same automation options as for other wet processing equipment are available for the Dry to Dry models. The unit is a convenient option for customers who want to simplify their process and increase output.

Custom Options

Because Modutek designs and produces all wet benches and related equipment in house without subcontracting, the company can use in house expertise to develop custom solutions for particular applications that may not fall within the standard option set. Customers can be assured that, no matter what the wet process application, Modutek engineers can propose a custom solution if the broad range of standard options is not suitable. For more information or for a free quote contact Modutek at 866-803-1533 or email [email protected].