Reliable contamination control solutions supporting clean environments and process stability in semiconductor manufacturing.
Chip manufacturing is a process of forming structures layer by layer on a silicon wafer. Thin-film deposition, resist coating, lithography, development and etching are repeated, with cleaning performed at multiple stages. Liquid filtration is used in water treatment, chemical transfer, photoresist delivery, polishing and wastewater reuse. Different steps use different liquids and require control of different contaminants.
Overview of Main Applications
01 | Water Pretreatment: Reduce the Particulate Load and Protect Downstream Equipment
Suspended solids and colloids in raw water need to be controlled before the water enters downstream purification equipment. Depending on feedwater conditions, pretreatment may include clarification, media filtration or ultrafiltration. Dissolved salts and other dissolved impurities are treated by appropriate processes such as reverse osmosis and ion exchange.
Bag and cartridge filters can be evaluated for locations where replaceable filter elements are suitable.
Bag filters can be fitted with filter bags of different materials and constructions for particle retention at the corresponding ratings. In addition to the filtration rating, selection requires checking dirt-holding capacity, bag sealing and the fit between the filter bag and support basket. Filter bags are available in various performance grades, and their application range should be based on actual retention data.
Cartridge filters can be fitted with PP depth cartridges, pleated cartridges or other types according to the filtration duty. Depth and pleated constructions differ in how they hold particles, their filtration area and differential-pressure performance. Selection should consider the particle distribution in the feedwater and the operating flow rate.
Bag filters, cartridge filters and ultrafiltration units can be evaluated separately at this stage. Guard filtration upstream of reverse osmosis provides protection against residual particles; higher suspended-solids loads should be handled by appropriate pretreatment processes.
02 | Final-Stage Ultrapure Water Filtration: Consider Cartridge Retention and Contamination
The evaluation of cartridges for final-stage ultrapure water filtration needs to cover fine-particle retention, initial cleanliness and performance changes throughout their service life.
Particle challenge tests are used to evaluate retention, while particle release during initial rinsing is also examined. Repeated testing over the service life is used to observe performance stability.These locations are evaluated in terms of dedicated cartridges, capsule filters or membrane modules. In addition to the filtration rating, applicable information on particle release, material extractables and rinsing is required.
The following three dimensions can be evaluated
03 | Cleaning and Wet Etching: Fully Review Wetted Materials
Material requirements for high-purity chemical systems include chemical resistance and the contribution of metals, ions and organic substances from the materials. Relevant specifications for high-purity polymers also address mechanical properties, chemical resistance and traceability requirements.
Cartridges require a comprehensive evaluation of the membrane, support layers, core, end caps, seals and housing, with checks performed in the following order:
Fluid Conditions
Specify the chemical name, concentration, normal and maximum operating temperatures, and cleaning conditions.
Material and Cleanliness Information
Confirm each wetted material and obtain applicable data on extractables, particle release and rinsing.
Validation with the Actual Chemical
Confirm how the test liquid, temperature and contact time correspond to the application conditions. Material tests performed with ultrapure water cannot directly cover all chemical operating conditions; each chemical system requires appropriate evaluation conditions.
04 | Photoresist: Particles, Gels and Microbubbles All Affect Delivery Quality
Photoresist filtration needs to control particles and gels while preserving the chemical properties of the resist. Microbubbles during delivery can also cause coating defects, so membrane wettability, filtration differential pressure, venting design and startup procedures are all important.
Photoresist and related photochemicals can use dedicated cartridges or capsule filters with different membrane materials.
Cartridge trials are recommended to be divided into two stages: liquid testing and wafer validation.
Liquid testing: Record target impurities, key formulation properties and startup-stage changes before and after filtration;
Wafer validation: Check coating and post-development defects.
05 | CMP Slurry: Observe Large Particles and Effective Abrasives Separately
The abrasives in chemical mechanical polishing (CMP) slurry participate in material removal. Abnormally large particles can cause scratches or nonuniform polishing. Filtration needs to control these particles while preserving the abrasive distribution required by the process.CMP filtration aims to reduce abnormally large particles and agglomerates while preserving the effective abrasive distribution. CMP-specific filtration products should be used and validated with the actual slurry.
The following three dimensions can be evaluated:
06 | Wastewater Reuse: Arrange Treatment by Composition, Then Determine the Filtration Location
Wastewater from backgrinding, dicing and CMP may contain fine process particles. Appropriate solid-liquid separation technologies can be used according to water quality. Dissolved inorganic and organic substances require suitable accompanying processes such as reverse osmosis, ion exchange or biological treatment.
Bag and cartridge filters can be candidate equipment for particle retention after upstream treatment.
Determine the filtration location based on wastewater segregation and the necessary treatment. Fine particles in backgrinding, dicing and CMP wastewater can be separated using suitable technologies such as ultrafiltration; dissolved contaminants in reclaimed water require appropriate purification processes.
The Following Five Areas Can Be Evaluated
About Harbory Filtration
Harbory Filtration’s liquid filtration products include stainless steel bag filters, cartridge filters, and matching filter bags and pleated cartridges. The specific configuration should be determined by the fluid, operating conditions and downstream acceptance requirements. For critical filtration locations involving direct wafer contact, the corresponding material cleanliness and process validation must also be completed.
Discuss Your Filtration Application
Share your process conditions and filtration requirements with our team.
Harbory Filtration
www.harbory-filtration.com
info@harbory-filtration.com
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