Wet Etch & Cleans

Pall Wet Etch clean Filters provide cleanliness solutions for different sterilization systems like recirculating chemical baths, high pressure jet sprays, and mechanical scrubbing systems. Effective filtration is essential for keeping chemical baths free of particles to clean the wafer surface effectively. Pall Wet Etch Clean filters aggressively eliminate impurities in the chemical baths that degrade the PV surfaces electrical properties.

Pall offers a wide choice of suitable filtration products for chemical, gas and water applications:

• Recirculating baths
• Single pass systems
• High velocity jet spray systems
• Quick dump rinse systems
• Mechanical scrubbing systems

Crystalline Silicon Cell Processing Chemical Filtration for Recirculating Baths

Pall filters actively reduce particle contamination on wafer surfaces during the cleaning and etching steps by creating a barrier that traps impurities. Protection of critical orifices (i.e., cleaning nozzles), is a crucial step in preventing such components from becoming clogged and resulting in unplanned equipment downtime. Fluid reclaim efficiencies can be maximized in a recirculating bath by placing an effective Pall filtration device in the loop. The usable life of the bath chemicals can be greatly extended through filtration. Filtration also leads to a much cleaner bath that can also improve the quality of the wafer by preventing defects from propagating to the wafer surface from contaminants in the chemicals. 

Filtration for Saw Damage Etching and Texturing

The Profile A/S Filters are especially designed to provide cost-effective solutions for hot, and/or highly contaminated, aggressive chemicals making them ideally suited for alkali texturization.

Filtration for Phosphorous Diffusion, Oxide Etching and Edge Isolation

Claris Series Filter Cartridges are engineered with an all polypropylene Graded pore structure for enhanced life. No surfactants, binders or adhesives are used in the conctruction leading to a safer media that will not have adverse chemical reactions.

Nexis T Series Filter Cartridges are similar to Claris Filters but can tolerate higher temperatures and differential pressures and therefore can be used in a variety of extreme process conditions.

Profile II Filters consist of an all polypropylene construction and high porosity for enhanced life

No surfactants, binders or adhesives are used in the construction leading to a safer media that will not have adverse chemical reactions.

Filtration for Anti-Reflective Coating

Molecular contamination in the hydrogen and silane gases used to form the antireflective coatings or amorphous silicon films can lead to many process problems, such as non-uniform coatings and other types of defects arising from particle generation. Gaskleen II Purifiers reduce moisture and oxygen from hydrogen and silane gases to < 1 ppb. The purifier also can remove trace levels of siloxanes and dopant metals such as As, P, Al and B from silane. Gaskleen Light Series Filter Assemblies are designed to provide state-of-the-art gas filtration for the photovoltaic market while minimizing cost.

Housing Recommendation

Megaplast Housings

• Available in polypropylene, PVDF and PFA
• Available in 10'' and 20''
• Available in manifold connections

Benefits:

• Enhanced process stability
• Increased area/process efficiency
• Extended chemical life
• Reduction in hard disk defects
• Reduced unplanned equipment downtime

Pall Wet Etch Clean filters eradicate defect causing contaminants from crucial cleaning systems. Contact a Pall expert and learn how you can better control your process conditions to improve operating efficiency and increase PV yields.