Multistep Filtration Helps Shanghai Semi Fab Improve Final Water Quality and Protect Against System Upsets
A major semiconductor manufacturer had poor water quality and periodic upsets from their municipal source. GORE® 0.1µm DI filters replaced the large pore size UF module guard filters, reducing baseline particle counts and maintaining good water quality through upsets.
Benefits
- Improved baseline particle counts during normal operations
- Added protection to maintain final water quality specification during system upsets
- No additional capital expenditure required
Situation
A major semiconductor manufacturer in Asia was experiencing periodic poor water quality from their municipal source. This was negatively impacting final water quality supplied to the fab.
The water system uses ultrafiltration modules as a final filter and large pore size guard filters to protect the UF from damage.
Spikes in particle counts from the municipal source were causing particle counts in excess of 4000 counts/liter @ 0.05 μm as measured after the UF module.
The manufacturer was considering installing an additional skid of UF modules to address the problem.
Solution
GORE® 0.1μm DI filters were selected to replace the large pore size guard filters, as they could provide higher retention of particles while maintaining the flow rate of the large pore size filters.
The GORE® Filters were tested by installing them in one of the fab's two final filter loops. The POR filters were kept in the other loop. Water quality was tested after the UF module in each loop and the results were compared.
Results
- GORE® Filters reduced the post-UF (baseline) particle counts from a range of 100 to 500 counts per liter at 0.05μm to a range of 50 to 200 counts per liter at 0.05μm.
- During periods of poor water quality from the source, the loop using GORE® Filters as the UF prefilters maintained good water quality of 500 counts per liter at 0.05μm.
FOR MICROELECTRONICS USE ONLY.
Not for use in food, drug, cosmetic or medical device manufacturing, processing, or packaging operations.