Quick Dump Rinse Tanks (QDR) are used to properly rinse semiconductor wafers, cassettes and other parts while conserving DI water. Semiconductor wafer and cassette cleaning, etching, and stripping applications using KOH / HF and other chemical residues must be completely removed including in blind recesses and pockets to ensure chemicals do not continue to process (etch, strip, etc). Continued chemical processing after removal from wet process equipment can result in over etching, stripping, failed wafer patterns and other semiconductor failures.
How a Quick Dump Tank Works
The quick dump rinser fills deionized (DI) or ultrapure water from the bottom of the bath through nozzle manifold ports that direct the flow upward and around wafer part surface. The upward spray under immersion removes particles, chemicals, etc from the part. The top of the tank has an overflow weir to discard the removed particulate and chemistry. When overflow is complete, the bottom quick dump door opens and the rinse water drains from the tank in a matter of seconds while nozzle sprayers on the top of tank keep the product wet with fresh, clean DI water during the dumping process. For high precision applications requiring extremely clean wafers, post process high flow cascade overflow rinse tanks to ensure all chemical and particulate is removed.
Example of Quick Dump Tank
Proper rinsing ensures:
- Stopping the chemical reaction (stripping, etching, etc)
- Clean rinse water dragged out on parts from chemical wet processes.
- Complete contaminant, chemistry and particulate removal from the wafer or part
3 types of rinsing used depending on customer application especially in the semiconductor:
- Cascade overflow rinsing: wafers and parts are completely immersed into rinse tank and continuous overflow of fresh DI water inlet from the bottom and overflow at the surface
- Spray rinsing: An operator uses a spray wand to spray DI or ultrapure water or spray manifold at the top and sides of tank spray parts.
- Quick dump rinsing: utilizes both spray and overflow rinsing for wet bench process equipment which water is quickly evacuated from the tank flushing particulate and contaminants away from wafer parts.
Cascade Overflow Rinse Tanks
Features and Options of Quick Dump Rinse Tanks
- The four sided overflow weir helps break the surface tension and removes particles from the process area.
- Minimal welds, corners, and sloped edges to prevent particle entrapment on tank surfaces
- Nitrogen N2 agitation bubbler
- Materials of Construction (application dependant): Polypropylene, Stainless Steel, PVDF, Teflon PTFE / PFA, PVC
- Resistivity monitoring to ensure rinse water quality and wafers, cassettes, and parts are properly rinsed
- DI water reclamation, recycling and reuse
- Flowmeter for volumetric control
- Hot DI Water compatible
- Four sided cascading overflow weir
- Standalone tank or build into full wet bench process line
- A touch screen PLC allows part specific rinsing programs controlling number of rinse, high flow cascade and dump cycles.
Advantages of Quick Dump Tanks for Wet Process Equipment
- Up to 80% DI water consumption reduction compared to overflow rinsing.
- Up to 75% faster process times thru rinsing chemistry from the wafer and cassette surfaces more rapidly
- Superior rinse performance of QDR tanks using surface spraying with less time and water
All our quick dump rinse tanks are sized to customer application, contact us to learn more about how quick dump rinse tanks can benefit your process.