How Quick Dump Rinsers Improve Silicon Wet Etching Results

Manufacturing lines in semiconductor fabrication facilities and research labs use corrosive chemicals to clean and etch silicon wafers. Depending on the semiconductor product, a silicon wafer may undergo multiple steps in baths containing chemicals such as hydrochloric acid or hydrogen peroxide. When the cleaning or etching process in a particular fabrication step is complete, the chemicals must be rinsed from the wafer before the silicon wafer can be processed further. Quick Dump Rinsers provide a quick and effective way of thoroughly rinsing the wafers without introducing new contaminants.

How Quick Dump Rinsers Work

Once wafers are placed into the rinser, powerful jets spray de-ionized water over the wafers to remove all traces of chemicals. As the rinse tank fills up, chemical residue and contaminating particles are flushed out and rise to the surface. A nitrogen gas bubbler system serves to agitate the de-ionized water further, removing additional contaminants from the surface of the wafers. An overflow weir allows the surface water to flush the chemicals and particles out of the tank. When the rinsing process is complete, the quick dump door at the bottom of the tank opens and the water drains out in a matter of seconds.

The key characteristics of a Quick Dump Rinser are rapid operation, complete removal of contaminants and avoiding the addition of new contamination. Rapid operation helps reduce the use of de-ionized water and saves process time. If traces of chemicals are not completely removed, etching of the wafer might continue and result in defective or low quality products. The same is true if particles are not eliminated or are added during the rinse. Since rinsing has to be carried out at the end of many process steps, Rinser performance is critical for product output quality.

Modutek’s DR Series Quick Dump Rinser Features

Modutek’s Quick Dumps Rinsers are designed to meet the needs of advanced semiconductor fabrication. Wet process semiconductor manufacturing facilities and research labs can use the Modutek rinsers as stand-alone units or integrated into a wet process manufacturing line. The rinsers work quickly and deliver completely clean wafers. They incorporate the following features:

  • Contoured vessel design
  • Nitrogen bubbler on all models
  • Natural polypropylene or PVDF (option) tanks, nozzles and fittings
  • Large machined dump door without gaskets or seals
  • 360 degree overflow weir

Modutek’s design minimizes de-ionized water consumption and reduces rinse times while ensuring effective rinsing. The tanks require a de-ionized water supply, a source of pressurized nitrogen and a 120 or 24 V AC power supply. Options include a reclaim system, Teflon nozzles, fittings and valves, and special process cover configurations. The rinsers are available in a variety of sizes.

How Modutek’s DR Series Rinsers Improve Silicon Etching Results

Semiconductor manufacturing makes use of ever smaller microstructures and circuit connections. During wet etching of the silicon wafers, even a tiny particle can block a circuit path or deform microstructure design. Modutek’s rinsers are designed and constructed to avoid particle contamination.

The contoured vessel and machined trap door avoid entrapment of particles in corners or in cracks around seals and gaskets. The nitrogen bubbler helps dislodge any particles remaining on the surfaces of the silicon wafers. The 360 degree overflow weir gets rid of contaminants in the surface water quickly and the polypropylene material avoids the addition of metallic particles from fittings.

Modutek’s DR Series Quick Dump Rinsers are state-of-the-art process rinsing modules that work quickly and rinse completely. Used together with wet bench stations from Modutek’s extensive line of silicon wet etching equipment they can deliver exceptional performance for semiconductor manufacturing facilities and research labs. Contact Modutek for a free consultation on selecting the best equipment that will meet your manufacturing requirements.

Improvements to the Silicon Wet Etching Process

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

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

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

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

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

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

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

Modutek’s DR Series Quick Dump Rinser

Modutek Quick Drump Rinser DR Series

Modutek’s DR Series Quick Dump Rinser

Throughout wafer manufacturing, few steps are as critical as the D.I. (deionized water) rinse cycle. In most cases, your product is exposed to more D.I. water than any other process fluid. For this reason, a truly effective rinsing system can contribute dramatically to the reduction of particles and defect densities. A considerable amount of time has been given to help you make this transaction into our DR series quick dump rinser easy and affordable. Whether it’s upgrading your existing rinsing line or installing new wet process station we have the plan that will work best for you.

Our overall DR series Quick Dump Rinser is designed with two major features. One: Easy installation into new or used equipment and two: Low DI water consumption due to our rinse features.

Modutek's Quick Dump Rinser during the spray cycleSuperior and consistent rinsing is achieved by (1) strategically located D.I water spray nozzles, (2) bottom filling (3) N2 agitation and (4) bottom fill that creates a vortex agitation in the rinse tank (optional).

The interior volume of the DR Series Quick Dump Rinser was reduced to minimum size relative to the wafer cassette. This, along with a 360˚ overflow weir and rapid dump time ensures that all large and small contaminants are quickly removed from the surface of the wafer and surrounding areas, thereby preventing recontamination of the wafer.

Modutek C15sa Rinser Controller is used in conjunction with the Quick Dump RinserModutek’s C15sa Rinser Controller is specifically designed for use with the DR Series Quick Dump Rinser wafer rinse system and provides a high degree of process flexibility. The user has the ability to program dump cycle, fill cycles, start cascade and spray delay. In addition, our C15sa controller has the ability to be programmed for resistivity and incorporates an access code which prevents tampering with the program.

In order to rinse to resistivity, the DR Series is used in conjunction with the Modutek Resistivity Monitor RM30a (optional feature). The RM30a has the ability to monitor resistivity and temperature inside the DR series rinser as well as incoming water into the wet bench. Once resistivity setting is reached inside the Quick Dump Rinser the rinse cycle discontinues at the next full level. This results in a process specific rinse, ensuring that a minimal amount of DI water is used.

Modutek Quick Dump Rinser during full rinse cycleIn addition to all of these features Modutek’s Quick Dump Rinser is designed for new or used wet bench installations. With this design you can easily upgrade your old rinser and not incur the cost of a new wet bench. The water savings and the increased throughput will help cover the cost of the overall upgrade. If you would like to learn more about Modutek’s Quick Dump Rinser and how it can improve your wafer manufacturing process, call 866-803-1533 or email [email protected].