Double-Stage RO + EDI Ultrapure Water Solution for Semiconductor Packaging & Testing Plants

1. Project Overview

Project Scale: Packaging & testing workshop with hourly water consumption of 15 m³/h. Processes include wafer dicing rinsing, pre-molding cleaning and pad cleaning. The production process imposes strict control on resistivity, TOC and trace metal ions; water quality fluctuations may cause chip leakage and packaging defects.

2. Designed Water Quality Standards (25℃)

Resistivity: 15~17 MΩ·cm

TOC ≤15 ppb

Single heavy metal ion ≤0.5 ppb

Particulates ≥0.1 μm: ≤5 particles per mL

Dissolved oxygen ≤25 ppb

3. Full Process Flow

Raw Water→Multi-Media Filter→Activated Carbon Filter→Sodium Ion Softener→Dosing Unit→5μm Security Filter→1st-Stage Reverse Osmosis→2nd-Stage Reverse Osmosis→EDI Feed Water Tank→EDI→Vacuum Degassing Tower→185/254 Dual-Wavelength TOC UV→Ultrapure Water Storage Tank→0.1μm Terminal Filter→Packaging Cleaning Station

4. System Highlights

Two-stage reverse osmosis performs pre-desalination to greatly reduce salt content of EDI influent and lower membrane stack load. EDI realizes continuous desalination via electric field, eliminating traditional acid-base mixed beds and cutting hazardous waste treatment & manual regeneration costs.

Dual-band UV degrades trace TOC, and vacuum degassing reduces dissolved oxygen to prevent pad oxidation. Ultra-precise terminal filters intercept ultrafine particles. All pipelines use EP-grade stainless steel and PVDF materials to avoid secondary ion contamination. A multi-parameter online monitoring system triggers automatic reflux protection for production lines upon abnormal water quality. The modular design supports direct expansion of RO and EDI modules for future capacity upgrades.