How Quick Dump Rinsers Improve Silicon Wet Etching Process

Quick dump rinsers provide fast and effective rinsing of silicon wafers from chemicals and particles. During semiconductor fabrication silicon wafers are etched with chemicals and particles, which have to be rinsed off to prevent continued etching.

Modutek's quick dump rinser uses de-ionized water to wash away all traces of chemicals while introducing no new particle contamination source. It uses state-of-the-art engineering techniques that allow it to reduce de-ionized water consumption while featuring a short rinsing time and particle reduction. The large trap door and the contoured rinsing vessel shorten dump times and promote laminar flow to rinse away contaminants. The machined dump door doesn't have any seals or gaskets that could entrap particles, and the smooth polypropylene construction of the tank ensures that it is not a source of new particle contamination.

Once the silicon wafers are placed in the rinser, de-ionized water jets rinse the chemicals from the wafer surfaces. The tank fills, bringing the rinsed contaminants to the surface where they leave the tank through the overflow weir. A nitrogen bubbler produces gas bubbles that rise through the water and remove additional particles and contaminants. At the final stage of the rinse cycle, the trap door at the bottom of the tank opens to drain the water.

The entire rinsing process is fast and thorough without introducing new contamination. The use of Modutek's quick dump rinsers can improve production and output quality. When quick dump rinsers work rapidly, effectively removing chemicals, particles, and contaminants leads to an increase of throughput and reduced chances of product rejection.

Rinsing is required after most of the wet process production steps, and any time saved with a quick dump rinser is multiplied by the number of times rinsing takes place in the semiconductor production process. Modutek's quick dump rinser provides these benefits by addressing overall semiconductor manufacturing requirements.

Modutek's quick dump rinsers provide additional benefits, such as reduced costs and faster production line operation. Reduced de-ionized water lowers costs, and an optional reclaim system can result in extra savings. Besides quick dump rinsers, Modutek also supports customers with full line of standard or customized silicon wet etching equipment.

For more details read the complete article, How Quick Dump Rinsers Improve Silicon Wet Etching Process. If you have questions, or would like to set up a free consultation, call 866-803-1533 or email modutek@modutek.com.

How Quartz Tanks Improve Wafer Manufacturing

Chemicals used in wet process wafer manufacturing need to be contained in process tanks that can resist etching, corrosion and remain inert. In some applications, a process may require heating, filtration or the regular addition of chemicals. Quartz tanks are made from semiconductor grade flame-polished quartz and are impervious to the acids and bases used in wafer processing. They minimize contamination of wafers from particles and can be supplied in heated and re-circulating models.

Wet bench processing of silicon wafers consists of fabrication steps such as etching and diffusion with cleaning required in between the steps. The wafers are “masked” to etch specific parts of the wafer to confine diffusion to certain target areas. Once each process step is done, the masking material must be cleaned off.

Cleaning the wafers completely without contamination is crucial. When the wafer is not clean and still has contaminants, even a single particle can result in a badly formed structure or conductor. When such malformations are incorporated into the final product, it can result in defective or lower-quality semiconductor components.

Modutek offers specialized quartz tanks that are made from semiconductor grade flame-polished quartz and are impervious to the acids and bases used in wafer processing. Quartz tank controls allow operators to program reproducible process environments and make sure temperatures and chemical concentrations are consistent. Heating, chemical spiking, and filtration are the three important areas for which specialized control systems are useful.

Heating – Modutek's high-temperature re-circulating baths and constant temperature tanks heat up rapidly with a temperature rise of up to two degrees centigrade per minute. Quick heating helps improve throughput and accurate temperature control helps ensure high-quality results.

Chemical spiking – Periodic spiking restores the chemical concentration of the chemicals to the desired effect. Modutek has developed an innovative “bleed and feed” spiking method for the sulfuric acid and hydrogen peroxide process.

Filtration – Modutek's quartz tanks can also reduce particle counts and wafer contamination. The quartz re-circulating tank can filter out particles down to 0.2 microns, improving output quality and reducing component failure rates.

The complete article, “How Quartz Tanks Improve Wafer Manufacturing” explains more details. If you have questions and would like to set up a free consultation, contact Modutek at modutek@modutek.com or call 866-803-1533.

How Megasonic Cleaning Improves Silicon Wafer Manufacturing Results

Semiconductor components that include processors, switches and memory chips have become so miniaturized, that even sub-micron foreign particles can block the formation of a conducting path or other key structural components. That is why removal of sub-micron particles during the manufacturing process is crucial to avoid defective products. These particles are usually removed by traditional cleaning and rinsing using aggressive chemicals. However, megasonic cleaning is the better alternative option in cleaning silicon wafers because it can remove even the tiniest particles.

Megasonic cleaning uses megasonic sound waves to remove contamination from surfaces of parts being cleaned. The sound waves in the cleaning solution create microscopic bubbles in the wave pressure troughs and collapse them in the wave peaks. When a bubble collapses, it discharges a tiny but powerful and energetic jet of cleaning solution that dislodges contaminants and particles from part surfaces. Modutek has partnered with Kaijo Shibuya Corporation, a world leader in Megasonic and ultrasonic cleaning systems, to create a line of Megasonic cleaning equipment suitable for use in semiconductor manufacturing.

Megasonic cleaning uses a wide range of frequencies. The right selection of frequencies is the key to optimum cleaning performance. Lower frequencies are used for less fragile devices, while higher frequencies are suitable for gentle cleaning of the more delicate parts or parts with soft surfaces.

And because semiconductor components often include very delicate structures and soft layers of deposits on the surface, only the highest frequencies deliver gentle cleaning to avoid damage and pitting to these fragile structures.

Modutek’s Megasonic cleaning system can clean at frequencies between 200 kHz and 2 MHz but generally operates at 950 kHz. The system delivers up to 1200 W of cleaning power and can operate with bath temperatures of up to 140 degrees centigrade. The system offer superior performance and can removal rate for particles down to 0.1 microns which improve semiconductor component yields, reduces the number of defective components and improves product quality.

For more details read the complete article “How Megasonic Cleaning Improves Silicon Wafer Manufacturing Results”. If you have questions after reading the article, or would like to set up a free consultation, contact Modutek at modutek@modutek.com or call 866-803-1533.