Changes to the SPM Process Improves Efficiency and Results

The sulfuric acid peroxide measure (SPM) is the process that effectively strips and cleans silicon wafers, however due to the decomposition of the hydrogen peroxide it suffers from instability. Heated baths can speed up the process, but they can affect the concentration of the hydrogen peroxide. Periodically adding the mixture with extra hydrogen peroxide, on the other hand, will maintain its concentration but it can affect the strip rate. As a result, the SPM mixture needs to be changed as frequently, and leads to high costs of chemicals and frequent downtime on wet bench stations.

Modutek has addressed the SPM issues with its new “bleed and feed” spiking system, which uses a double clean-and-dirty tank process. This newSPM strip and clean process starts by draining a programmable amount of mixture prior to each process step. Next, a programmable amount of sulfuric acid is added to a clean tank. Now both tanks have the programmable amount of hydrogen peroxide.

With the “bleed and feed” method, a complete chemical change is now only required about once a week as compared to two or three times a day. It also helps in reducing downtime and enables the process to get up again quickly. Result is less frequent changes and use of costly chemicals.

The “bleed and feed” system is also PLC-controlled, and the periodic adding/spiking of chemicals enables the mixture to be used continuously for longer periods of time. In addition this updated process is more efficient in delivering better cleaning and stripping performance.

For additional details about the SPM process upgrade on Modutek’s wet bench stations, read the complete article entitled “Changes to the SPM Process Improves Efficiency and Results.” If you need more information or have questions, please send an email to modutek@modutek.com or call Modutek at 866-803-1533.

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

After cleaning, a silicon wafer needs to be effectively cleaned and dried with no particle contamination. Clean wafers are important to avoid errors in the next processing steps to produce devices that are of superior quality and free from defects. Using the single chamber HF-last and IPA vapor dryer show a considerable reduction in wafer substrate particle counts.

By the final stage of silicon wafer cleaning, the silicon oxide layer has to be removed and the cleaned wafer dried free from contaminants. However, transferring the wafers from the HF etching process to a separate drying chamber will likely cause the wafers to pick up particles.

Modutek now has a solution to this problem: the single-chamber HF-last and IPA vapor dryer, which can help to significantly reduce the particle count on wafer substrates.

In the single chamber process, Modutek uses IPA vapor drying in a free-standing unit with one DI water rinsing and drying. This method, also called the Marangoni drying technique, results in clean wafer substrates -- having no contamination or watermarks.

Modutek has 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 ratio is controlled and provides an etch to bare silicon. When the silicon is etched, it is then rinsed to a controlled pH level. Once the appropriate pH levels are reached, it is then followed by the IPA drying process without moving the silicon wafers. This results in the low particle count on the wafer.

Initial field results from the single chamber HF-Last IPA dyer that Modutek has supplied to customers are showing outstanding results. Within the 0.3 to 5 micron range, fewer than 20 particles (adders) were added to etched substrates which are substantially below what was achieved in previous processes in this field trail.

For more details read the complete article “Advantages of HF-Last Etching and IPA Drying in One Chamber” to learn more about Modutek’s IPA vapor dryers. Call Modtuek at 866-803-1533 or send an email to Modutek@modutek.com if you have questions or would like to get a free consultation.

How Megasonic Cleaning Improves the Silicon Wafer Cleaning Process

The need for effective elimination of contaminants from silicon microscopic circuits has become increasingly important. Megasonic cleaning, which uses sound waves in the MhHz range generated in the cleaning solution will remove particles as small as 0.1 µm which significantly improves cleaning effectiveness.

The traditional cleaning methods of using harsh chemicals may leave small contaminants in place, and lead to the inferior quality or possibly, even failure of the semiconductor components being produced.

The megasonic cleaning system consists of a high-frequency generator, transducers, and cleaning tank that holds the cleaning solution (such as water or a mild cleaning agent) and the parts to be cleaned. The transducers convert the electric signal (which comes from the generator) to sound waves in the MHz frequency range which travel through the cleaning solution. These sound waves generate microscopic cavitation bubbles in the low-pressure wave troughs. These bubbles will then collapse in the high-pressure peaks, and as a result, they produce tiny jets of water. These resulting jets, when hitting the wafer, will dislodge any particle that adheres on the wafer's surface.

The particles will be carried away by the water currents. There are millions and millions of tiny bubbles which ensure that the silicon wafer is thoroughly cleaned. The bubbles can even penetrate into holes, curves, crevices and other microscopic structures, leaving the surface of the silicon wafer completely cleaned.

Modutek’s Megasonic Cleaning System, developed together with megasonic and ultrasonic technology leader Kaijo Corporation, is a superior alternative to the traditional cleaning methods as it only uses sound waves in the MHz range generated in a water cleaning solution. It can help remove particles down to 0.1 µm in size, to prevent them from affecting the silicon fabrication process. Plus, it improves the overall cleaning performance.

Read more details in the recent article titled “How Megasonic Cleaning Improves the Silicon Wafer Cleaning Process” for additional information. If you have questions, contact Modutek for a free consultation or quote or send them via email at Modutek@modutek.com or call 866-803-1533.

Wet Processing System for Solar Cell Manufacturing

Solar cell manufacturing facilities and research labs use wet processing equipment to etch and clean solar cell silicon wafers. Removal of wafer saw damage, silicon wafer texturing, chemical polishing and cleaning of the wafers with reliable and safe wet processing systems is an important factor to increase productivity and high quality output.

Modutek offers the latest wet bench and ozone cleaning technology to meet client requirements, whether they want to purchase standard systems or customized solutions. Modutek provides wet processing systems and equipment to a number of manufactuers in the solar cell industry.

Silicon Wafer Saw Damage Removal
When solar cell silicon wafers are cut they the surface will be damaged with an uneven crystal structure and damaged crystal lattice. These wafers are soaked in an etching bath that lifts a thin layer of damaged crystal, leaving a smooth uniform surface. Modutek’s wet processing equipment provides high throughput and accurate controls for this process.

Silicon Wafer Texturing
Solar cell silicon wafers absorb light and convert it into electricity more effectively when their front surface is etched with a microscopic texture.

For monocrystalline silicon, an etching bath lifts small pyramid shapes from the silicon's surface, which leaves a smooth, even consistent texture. Multi-crystal silicon, on the other hand, can be etched in the same manner, but the result is not as smooth because of crystal's different orientation. Available alternative solutions include ion-etching and masks.

Chemical Polishing
After the front, the rear side and the edges of the cell are polished by placing it in an etching bath. Polishing them improves the internal light reflection.

Ozone Pre-Cleaning
The cutting of silicon wafers with a wire saw uses a slurry applied to the wires, leaving the wafers contaminated with the slurry. To clean them, Modutek's Ozone Cleaning Process uses ozone dissolved in a mild solution. This cleaning process yields efficient cleaning at a lower cost.

Modutek’s wet Processing System is an ideal solution for solar cell manufacturers. Discover how Modutek can assist your company by reading our complete article titled “Wet Processing System for Solar Cell Manufacturing. Contact Modutek for a free quote or consultation to discuss which equipment to use for your application.

How to Select a Supplier from Your List of Semiconductor Equipment Manufacturers

Choosing a supplier from your list of semiconductor equipment manufacturers means you’ll have to look at key factors, such as:

·         Company experience and expertise - Selecting the right semiconductor manufacturing equipment supplier will affect future productivity and output quality. In this regard, it is imperative to go for a more experienced company with a wealth of expertise in this department.

·         Customization capabilities to meet customer requirements - Manufacturers differ from one another and have their own specifications regarding the installation or upgrade of the components. Sometimes the purchased equipment needs to interface with existing systems, and sometimes the physical setup of the production facilities is a limiting factor in what can be installed. Proposed equipment often has to be customized to some degree and the supplier needs to have the experience and capability to adapt their standard solutions to specific situations.

·         Equipment reliability – Ask your supplier for references and reliability statistics regarding the equipment you have purchased. Suppliers should provide details on hours of scheduled maintenance downtime, estimates of unexpected downtime as well as records of actual installations. It’s also a good idea to check with some references who are not direct competitors of your company to verify the information from the supplier.

·         Warranties, service and customer support - It is extremely important to ask for a written guarantee from your chosen supplier before you sign a contract with him. Thoroughly read the warranty and make sure that all the details (service personnel, customer support, etc.) are included. A manufacturer who hires his own personnel -- as opposed to subcontracting other employees -- is a good indication of a good supplier with a competent service staff/support.

Once you have found the ideal semiconductor equipment manufacturer/supplier, you will be able to look at cost of ownership and pricing to make your final decision. Read the complete article titled “How to Select a Supplier from Your List of Semiconductor Equipment Manufacturers” to learn how Modutek can help you. If you have questions after reading the article, please call 408-362-2000.

Tips on Selecting Chemical Delivery Systems for Your Application

Chemical delivery systems handle the chemical distribution required to maintain a variety of industrial processes. Corrosive or hazardous chemicals are securely stored and delivered to the process in specific concentrations or mixtures.

Chemical delivery systems integrated in processes like semiconductor manufacturing using wet bench equipment, allow safe operation with accurate amounts and quick change from one chemical to another. Chemical delivery system design needs to utilize correct storage methods and provide customization to meet the requirements of specific applications.

The list below includes specific factors that should be considered in selecting chemical delivery systems for your application:

·         How much of a particular chemical is used in the process?

·         How does the system calculate the required chemicals and how is the software for calculations supported?

·         What are the control options and do they integrate easily and well with wet bench controls?

·         What safety, error and leak detection features are available?

·         Is the system flexible enough to adapt to specific process requirements and can the supplier undertake such customization?

Apart from these questions, the supplier should have an excellent reputation and a wealth of experience in designing and handling chemical delivery systems.

One such company, Modutek Corporation, has vast experience designing and constructing chemical delivery systems that meet customers' specific requirements. It has a wide range of storage options from large volume storage to drums to carboys. These chemical delivery systems integrate seamlessly with the company's own wet bench stations and can typically work with wet benches from other companies. Modutek's chemical delivery systems are also safe, reliable, provide excellent performance and quick changeovers, and are also customizable to a customer’s specific requirements. Modutek has the internal expertise to evaluate customer requirements and will make appropriate recommendations that best support the application. Contact Modutek by email Modutek@modutek.com to learn more or read the complete article titled “Tips on Selecting Chemical Delivery Systems for Your Application.”

Chemical Delivery Systems That Meet Your High Tech Manufacturing Requirements

Modutek designs and develops custom chemical delivery systems to meet the specific requirements of manufacturing customers. These customers consist of industrial and research facilities who use chemicals for their processes and need a reliable and safe chemical system to store chemicals for ready use.

Typical applications of these systems include wet processing stations, wet benches, fume hoods, plating stations, precision cleaning stations, and acid exhaust hoods.

These custom chemical delivery systems feature all-Teflon fluid paths with double containment cabinet construction and leak detection. All chemical delivery is automated with a touch screen which provides important data including levels and alarms. Modutek's proprietary Solid Works Simulation Professional and SolidWorks Flow Simulation software allows customers to mix chemicals and perform delivery calculations to their specifications.

Modutek's chemical delivery systems are built to the highest standards and according to the customer's preferences. Customers can also request to be present at final testing at Modutek’s facility to ensure that the equipment meets all their specifications and they are fully satisfied with the results.

The advanced technology and high quality components used in Modutek’s chemical delivery systems reduce customer costs, reduce hazardous waste, and improve productivity and higher throughput. They are also safe and reliable, which helps customers achieve performance and productivity goals. Modutek’s chemical delivery systems can also be designed specifically to meet customer specifications.

For a free consultation or quote on selecting a chemical delivery system call Modutek at 866-803-1533 or email Modutek@modutek.com. You can read more details about Modutek’s chemical delivery systems by reading the blog article on the main site entitled “Chemical Delivery systems That Meet Your High Tech Manufacturing Requirements.”

Silicon Wafer Etching Processes for Wet Processing Applications

Manufacturing semiconductor components like processors and integrated circuits relies on silicon wafer etching of various processes including KOH etching to generate the required structures and connections.

Modutek's wet benches and other equipment can be used for a wide range of wet processing applications, which include:

KOH Etching – This involves the use of potassium hydroxide (KOH) in etching silicon wafers. This process is used to create microscopic structures in the silicon. It is important to note that KOH etching is a repeatable process that is inexpensive and etches quickly. Modutek's PFA Teflon tanks of their TFa or TT series are suitable for this etching application.

Silicon Nitride Etch – This is deposited on the silicon wafer in a thin film form and is etched with a hot phosphoric acid. It is used as a masking material in the fabrication of integrated circuits. Modutek's silicon nitride etch baths are suitable and safe for supporting this etching process.

Piranha Etch – This is used to clean silicon wafers during the semiconductor manufacturing process. The cleaning agent in this application consists of a mixture of sulfuric acid and hydrogen peroxide. Modutek can evaluate the customer's specific cleaning requirements and propose suitable solutions from its vast product line of wet processing equipment.

Metal Etch - Etching metals such as aluminum, gold and copper can be challenging process. Effective etching depends on selecting the right chemicals to use with the process. Modutek's vacuum metal etcher was developed and designed for precise wet etching of aluminum layers.

Gallium Arsenide (GaAs) Etch – Modutek's wet process solutions can handle the etching of Gallium Arsenide, which is used in the manufacture of integrated circuits and other electric and electronic devices. The solutions used consist of hydrogen peroxide, usually combined with sulfuric, hydrochloric, and phosphoric acids.

Modutek’s Wet Bench Solutions deliver reliable, repeatable results that are safe and accurate. For a free quote or assistance in selecting the right equipment for your silicon wafer etching process, contact Call Modutek at 866-803-1533 or send an email to Modutek@modutek.com. You can learn more about Modutek’s silicon wafer etching processes by reading “Silicon Wafer Etching Processes for Wet Processing Applications.”

Silicon Wafer Strip Solutions for Wet Processing Equipment Applications

 Modutek Corporation offers a wide range of wet processing equipment that is also customizable to deliver solutions for specialized applications. Silicon wafer strip solutions, the company can deliver various types of equipment that will support the following applications:

Silicon Nitride Strip
The silicon nitride strip removes silicon nitride from silicon wafers containing integrated circuits in a hot acid bath. The main factors for a high quality result are the selectivity of the bath strip solution along with consistently repeating all the process variables. 

The Modutek Nb series silicon nitride etch bath regulates the bath temperature while adding de-ionized water to control the water-to-acid ratio which provides the desired selectivity and repeatability of the process.

Resist Strip
For the photoresist strip, Modutek offers and advanced ozone cleaning process which can clean, etch or strip silicon wafers without the use of harsh chemicals. Thus this process is lower in cost and is also more environmentally-friendly.

Oxide Strip (Buffered Oxide Etch - BOE)
Modutek’s F Series filtered sub-ambient circulation baths for BOE applications can reduce acid use while removing particles and improving yields.

Solvent-Based Resist Strip
Modutek's SFa series temperature-controlled stainless steel recirculating baths can support a vast range of solvents such as IPA, acetone and resist strip solutions.

SPM Photo Resist Strip
Modutek's QFa high temperature recirculation quartz baths can handle photo resist strip using sulphuric acid and hydrogen peroxide mixture for the SPM processes.

Process engineers who are considering various silicon wafer strip solutions can rely on Modutek to provide the appropriate wet processing equipment for their application. 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. You can read more details about Modutek’s silicon wafer solutions by reading the article entitled “Silicon Wafer Strip Solutions for Wet Processing Equipment Applications.”

How Modutek Supports Customers Using Semiconductor Manufacturing Equipment

Modutek Corporation tailors its line of semiconductor manufacturing equipment to meet the specific requirements for each client. Modutek's experienced service teams and customer support ensures that their equipment installations perform efficiently, deliver high throughput and experience low levels of downtime. Here are the ways Modutek supports customers using its wet processing equipment:

1. Equipment testing
Modutek conducts final acceptance testing (FAT) of equipment at its facilities in San Jose, CA. Clients can come to Modutek’s facility during this verification process to review of the final testing. Customer site acceptance testing (SAT) includes onsite start-up training with experienced Modutek personnel showing operators how the equipment works. In addition follow up operational training can be provided to facility managers and any other customer personnel.  

2. Service contracts
Modutek provides service contracts to make sure that the equipment is operating optimally and that all controls and adjustments work according to specifications. Modutek offers service contacts for both new and used equipment.

3. Preventive maintenance contracts
Modutek offers preventive maintenance contracts to help ensure that the client's equipment is continues to work optimally. Service checks on Modutek’s equipment as well as equipment of some competitors can are done to detect problems that could slow production, affect quality or lead to unexpected downtime.

4. Field service and support
Besides testing, training and service contracts, Modutek also offers field service for customers who are in need for repairs or upgrade for their equipment, or for clients who want more customizable parts to facilitate the improvement of their process.

To learn more about how Modutek can support your company’s needs read the complete article on the site titled “How Modutek Supports Customers Using Semiconductor Manufacturing Equipment.” You deserve quality service and support from your semiconductor manufacturing equipment supplier. Call Modutek to get free quote or consultation at 866-803-1533 or send an email to Modutek@Modutek.com.  

Silicon Wafer Cleaning Solutions for Wet Processing Applications

Modutek Corporation designs, manufactures, and delivers standard as well as customized silicon wafer cleaning equipment for semiconductor manufacturing facilities and research labs. Their silicon wafer cleaning equipment provides effective and efficient contaminant and particle removal to promote high yields and improved throughput. The following cleaning processes are supported:

• RCA Clean - This is based on a cleaning system developed by RCA Corporation. The solution consists of water, ammonium hydroxide, and hydrogen peroxide in appropriate amounts. The system removes organic impurities and leaves a thin layer of oxidized silicon on the silicon wafer's surface.
• Standard Clean 1 and 2 - This process prepares the silicon wafer for the next processing. The RCA cleaning process is carried in two steps:
  1. Standard Clean 1 (SC1) - It uses AMP (ammonia/peroxide mixture) solution of the RCA cleaning method to remove the organic particles.
  2. Standard Clean (SC2) - It uses the HPM (hydrochloric acid/hydrogen peroxide mixture) solution to remove metallic ions. These two steps prepare the silicon wafer for additional processing.
• Piranha Etch Clean - This cleans hard-to-remove or large amounts of organic materials. The solution -- consisting of hydrogen peroxide and sulfuric acid in measured amounts -- is used to clean silicon wafers and hydroxylate surfaces. This mixture is highly corrosive and needs to be handled with caution.
• Pre-diffusion Clean - This is the final and very critical step before the silicon wafer goes into the diffusion furnace. Make sure that the wafer is completely free from contaminants and particles; otherwise they would disrupt the diffusion process and will lead into a low-quality or defective semiconductor output.

For more details on the wafer cleaning solutions supported by Modutek read the article titled "Silicon Wafer Cleaning Solutions for Wet Processing Application" on the website. If you want a free consultation or quote on selecting Silicon Wafer Cleaning Equipment for your application, call 866-803-1533 or email Modutek@Modutek.com.

Tips on Selecting the Right Options for Your Wet Bench Equipment

Modutek wet benches consist of white polypropylene construction with 304 stainless steel construction available for solvent applications. They can be built to any size and length depending on a customer’s requirements. The wet benches include safety features such as safety interlocks, emergency power off buttons, PVC safety shields, and wiring to NFPA 70 and 79.

Fully-automated wet bench stations use SolidWorks Simulation Professional and SolidWorks Flow Simulation software to optimize the semiconductor fabrication process and its performance. This eliminates human operator error by calculating the chemical dosage and operating the station to optimize process performance.

Semi-automated stations have some of the advanced features and precision of an automated station without the higher cost of the fully automated station. Customers can enjoy the benefits of process uniformity and precision of robotic controls as well as the SolidWorks Professional and Flow software at a reduced cost.

Manual wet benches are the most cost-effective way to get the safety features and operating characteristics of the Modutek wet process equipment family. These stations provide an effective start for customers to use wet process equipment. They can later add more automation features into these stations.

Solvent stations have a 304 stainless steel construction with fire suppression. They are available with the same fully automated, semi-automated and manual station options as Modutek’s other wet processing stations. These are for customers with applications that use acetone or IPA or want to do photo resist stripping or EDP etching.

Time-saving dry to dry wet process equipment removes transfers and increases throughput and yield. Customers who want to simplify this process may choose this equipment. Read more details in the article on the site titled “Tips on Selecting the Right Options for Your Wet Bench Equipment.”

Modutek at Semicon Conference in China

Modutek Corporation, provider of leading-edge wet benches and wet process equipment, will have a factory representative at the Semicon Conference in Shanghai, China on March 15 to 17, 2016. Modutek will join their China Rep Laserwort in Hall N3 at booth 3401. Those who are interested in Modutek's wet benches and wet process equipment can stop by the booth to learn more about the company's Automated, Semi-Automated and Manual Wet Bench Process Stations, which feature several applications and benefits like KOH etching, quartz cleaning, ozone etching and more.

Modutek also provides IPA vapor drying and Megasonic cleaning equipment for your manufacturing applications. Aside from that, eco-friendly acid neutralization systems and air scrubbers are also all available with all their equipment.

For more information about the Semicon Conference in China, refer to this website at www.semiconchina.org. You can also read more at “Modutek at Semicon Conference in China.”

Wet Processing Equipment Applications

Modutek provides technologically advanced yet cost-effective wet processing equipment and solutions that produce high-quality output. Applications include wafer etching, cleaning, drying, metal etching and stripping. Particular solutions include KOH etch and nitride etch.

The rotary wafer etching system has the ability to etch, clean, reclaim, develop, and strip semiconductor wafers and substrates. It features a dual tank design with a transfer between tanks for etching and then cleansing or rinsing.

Modutek’s vacuum metal etcher can etch aluminum layers on semiconductor wafers with high precision. It is fully automated, and etches aluminum in a vacuum to remove hydrogen bubbles that impede the etching process and generate "snow" and bridging of the etched wafers.

Modutek’s IPA Vapor Dryer cleans dry wafers without creating water spots. It can utilize ozone in the drying chamber to remove organic contaminants. Most drying cycles can be done in 10 to 15 minutes.

Modutek's state-of-the-art wet processing equipment is designed to meet the applications of any semiconductor manufacturing or research facility with either standard products or custom-designed solutions. If you need help with selecting the right equipment for your application, contact Modutek at 866-803-1533.