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.

The Advantages of Using Modutek’s Quartz Tube Cleaning Stations

The Advantages of Using Modutek's Quartz Tube Cleaning StationsAfter a quartz tube is used in a high-temperature semiconductor manufacturing process, it has to be cleaned thoroughly to remove contamination. Process steps such as diffusion leave traces of diffused material on the tube and the high-temperature furnace leaves contaminants. A Quartz tube cleaning station removes the surface contaminants and leaves the quartz tube clean and free of particles, ready for its next use.

Effective Quartz Tube Cleaning Is Critical for Output Quality

Quartz tubes are used as an inert container for semiconductor manufacturing processes such as vapor deposition and diffusion. The wafers inside the quartz tube are inserted into a furnace that can reach 1000 degrees centigrade. The semiconductor characteristics and the circuit paths of semiconductor components are created during these process steps. After use, the quartz tube surface has deposits from the furnace and from the process. Before it can be used again, the deposits have to be removed and the quartz tube has to be cleaned in a way that minimizes the particle count on its surfaces.

In a quartz tube cleaner, an acid spray dissolves the surface contaminants and washes them away. The clean tube is then rinsed with de-ionized water and dried carefully without introducing any new contaminating particles. Because quartz tubes are fragile and because handling them introduces new contamination, a degree of automation for quartz tube cleaning can be beneficial.

Minimizing the particle count is especially important for subsequent semiconductor manufacturing steps such as masking or etching. When micro-structures are etched into the wafers or current paths are created on masked wafers, even a single particle can affect a microstructure or block a current path. Such effects can lead to defective or poor quality semiconductor components. Manufacturing facility throughput is reduced by large numbers of rejected products and output quality can suffer.

Modutek’s Quartz Tube Cleaners Deliver Substantial Benefits

Quartz tube furnaces are typically placed in several locations along a semiconductor production line and each requires reliable cleaning. The benefits of Modutek’s quartz tube cleaning stations include the following:

  • Customization. Modutek designs and builds its quartz tube cleaning stations in house. As a result, the company can easily customize each station to exactly meet specific requirements.
  • Rugged, reliable construction. Made from white polypropylene, the cleaners feature a rugged tube roller system and powerful cleaning nozzles that ensure complete coverage.
  • Safe operation. Operators are protected with PVC safety shields and safety interlocks. The systems include emergency off mushroom buttons.
  • Variety of Options. Modutek offers many options, including hot N2 drying, acid holding tanks and acid mixing, lift stations and onboard bottle washers.
  • Automation. The cleaners can be operated manually or fully automatic. If required, different steps can be automated while others can be carried out manually. Manual operation can test out the cleaning process and then run it fully automated.

Modutek horizontal quartz tube cleaners deliver reliable cleaning with the degree of automation ideal for the specific process application. Handling of the tubes is minimized and an extremely high degree of cleanliness is achieved consistently.

Modutek Designs, Builds and Supports the Equipment Needed for an Application

With its in house expertise and extensive experience in semiconductor manufacturing equipment, Modutek can analyze a manufacturing process and provide equipment to fulfill the process requirements. The complete line of Modutek wet processing equipment is developed in house so that the design and manufacturing knowledge stays in the company. As a result, Modutek can design and build equipment to meet specific needs. Customers can ask for a free consultation and select standard stations from the Modutek wet process line or receive customized equipment that fulfills their requirements.