Batch wet benches process multiple wafers together in chemical baths, the traditional approach to wet processing. Capacity: Typically 25-50 wafers per batch (one or two carrier loads). High throughput. Process flow: Wafers in carrier move through sequence of chemical tanks and rinse tanks. Tank sequence: Often: chemical treatment, overflow rinse, chemical 2, rinse, dry. Automated transfer between tanks. Advantages: High throughput, lower cost per wafer, established technology, good for stable processes. Disadvantages: All wafers get identical treatment, chemical aging affects uniformity, particle transfer between wafers, batch-to-batch variation. Chemical management: Monitor and replenish bath chemistry. Replace baths on schedule or based on analysis. Cross-contamination: Particles or contamination can transfer between wafers in same batch. Applications: Standard cleans, oxide etches, metal cleans, processes where tight uniformity is not critical. Trends: Single-wafer processing replacing batch for many critical processes at advanced nodes. Equipment manufacturers: TEL, Screen/DNS, KEDI, JST.