Key Measures for Particle Control in Wet Cleaning Equipment—Source Prevention and Control

In semiconductor wet cleaning processes, effectively controlling particulate contamination is a core challenge to ensuring wafer yield and device performance. Particles can cause device short circuits, open circuits, or performance degradation. Achieving low particulate levels requires a systematic approach from multiple dimensions, including source prevention and cleaning process optimization.

Source Control: Minimizing Particle Introduction

• Ultra-pure Media Management: Ensuring the purity of ultrapure water (UPW) and chemicals is fundamental. Strictly select high-purity suppliers and regularly audit their quality control systems.
• Precision Filtration System: All liquids entering the equipment must undergo rigorous filtration. Key measures include installing ultra-low particulate release (ULPA) terminal filters with 0.05μm or smaller pore sizes before the process tank or spray arm inlet, and using multi-stage series filtration (e.g., 1μm→0.1μm) to capture particles in stages to protect the terminal filter.
• Filter Management: Establish and strictly implement procedures for filter replacement, flushing (removing trapped particles), and verification. Closely monitor pressure drop changes and regularly perform particle count tests to confirm effectiveness.
• Chemical Delivery System: Chemical delivery pipelines and tanks must use high-purity inert materials (such as PFA) to ensure smooth surfaces, no particle release, and maintain positive pressure sealing to prevent environmental particle intrusion.
• Low-Release Material Application: All components in contact with media and wafers (tanks, spray arms, pipelines, nozzles, baskets/carriers) must use low-particle release materials (such as high-purity quartz, PFA, PTFE, PVDF, specific PP/PE) to avoid easily corroded or shedding materials.
• Surface and Structure Optimization: Contact surfaces require extremely high surface finish (low Ra value) to reduce particle attachment points. Equipment structural design (pipelines, valves, joints) must avoid dead corners and stagnant areas, and welding connections are preferred.
• Key Component Selection: Select low-shear, low-particle-generating pumps (diaphragm pumps, specific centrifugal pumps) and valves (diaphragm valves, bellows valves) to avoid generating metal friction particles.
• Wafer Carrier Control: Wafer boxes/baskets are a significant particle source. They require low-release material (such as PEEK) design and the establishment of dedicated cleaning, inspection, and replacement procedures to minimize contact points with the wafer.
• Stringent Environmental Protection: Equipment must be placed in a high-level cleanroom (such as ISO Class 1/3), with local laminar flow purification units (FFU) set up in key areas such as wafer transfer/unboxing. Maintain positive pressure inside the equipment to prevent contamination, and personnel must strictly adhere to cleanroom regulations.

Kexin Micro Company - Leading the Innovation of Semiconductor Cleaning Technology

For more technical details, please contact our technical consultant: 13861996325!

▲Technical Consultation ▲Follow Kexin Micro's WeChat Official Account