Silicon wafer cleaning is an essential and critical part of semiconductor manufacturing. Particles must be removed from the wafer substrate during processing without damaging the delicate microcircuit structures. This will result in defective semiconductor components or low-quality output.
In megasonic cleaning systems, a megasonic frequency generator creates high-frequency sound waves in a liquid via a transducer which is submerged in a cleaning tank. The sound waves are compression waves that appear either in high-frequency peaks or low-frequency troughs. The low-frequency troughs produce cavitation bubbles which break down in high-pressure peaks. These bubbles provide the cleaning action for removing contaminants that are on the surface of the wafer. Low ultrasonic frequencies (20 to 40 kHz) produce large, high-energy bubbles which clean more robust surfaces, while high ultrasonic frequencies produce smaller bubbles, ideal for cleaning delicate components.
The megasonic cleaning technology used in the process will effectively remove sub-micron particles and contaminants without damaging or altering the wafer’s surface. Selecting the right frequencies and power levels is essential for effective cleaning results. Modutek incorporates the Kaijo Corporation high-frequency Megasonic Cleaning technology into its wet bench process equipment.
Kaijo’s megasonic generators in Modutek’s wet benches operate at 950 kHz in the standard version. Other frequencies are also available for a variety of cleaning applications. Modutek has included Kaijo’s megasonic cleaning system in both direct and indirect bath designs. Semiconductor facilities can use Modutek’s wet benches which incorporate the use megasonic cleaning technology to effectively improve yields. Benefits of using the technology include faster cleaning time, higher cleaning effectiveness, and lower use of costly chemicals and their disposal.
If you have questions about using Modutek’s wet bench stations which incorporate megasonic cleaning technology, call Modutek or email Modutek@modutek.com. For more details read the the full-length article entitled “How Megasonic Cleaning Technology Improves Silicon Wafer Yields.”