Small Changes Can Make a Big Difference in Stability and Throughput
When it comes to Spin Rinse Dryers (SRDs), precise rotational speeds are critical for both performance and longevity. A recent test by SITEK Process Solutions demonstrated just how much impact a small RPM adjustment can make — in this case, turning a visibly wobbly process into one that runs silent and smooth.
During a customer rebalancing project, the rotor was initially tested at 500 RPM during the rinse step. At this speed, the process exhibited slight vibration — not uncommon for heavily loaded cassettes. However, when the RPM was increased by just 100 (to 600 RPM), the difference was immediate. The rotor ran quietly, the movement stabilized, and the entire process became smoother.
The Role of Wafer Nesting
This improvement occurs because of wafer nesting — the point at which the wafers settle firmly into the cassette slots under centrifugal force. Once the wafers nest, they stop shifting or vibrating against the cassette, eliminating most of the noise and imbalance.
The proper nesting speed depends on wafer mass, cassette design, and load configuration, but even a modest increase in RPM can ensure the wafers seat securely during rotation.
Heavier Substrates Require Higher RPMs
For customers processing non-traditional or heavier substrates, achieving proper nesting becomes even more important. Heavier materials generate greater inertia and require higher centrifugal force to stabilize. Running at a slightly higher RPM ensures the wafers are fully nested, preventing vibration, reducing stress on bearings, and improving process consistency.
Rebalancing and Process Optimization
Rotor rebalancing also plays a key role in maintaining smooth operation. As shown in the recent SITEK demonstration, a previously refurbished rotor was successfully rebalanced to accommodate additional substrates — increasing throughput without compromising stability. Once tested at optimized RPM values, the rotor performed like new, even with a heavier cassette load.
Optimize Your RPM with SITEK
If you’re unsure about the ideal RPM settings for your process recipes, SITEK Process Solutions can help. Our engineers have decades of experience with Wet-Processing Equipment, specializing in SITEK / Semitool / Rhetech Spin Rinse Dryers and related wafer cleaning tools.
Whether you need help fine-tuning your recipes, rebalancing rotors, or upgrading your controllers, we’ll ensure your SRDs operate as smoothly and efficiently as possible.
📧 Contact us today: sales@sitekprocess.com
📞 +1 916 797 9000
🌐 www.sitekprocess.com
