Semiconductor Cleaning Flow Field Design

The Core Goal of Semiconductor Cleaning Is “Particle Control”

Semiconductor processes have extremely low tolerance for contamination. Even microscopic particles that are invisible to the naked eye may affect circuit yield.

Therefore, the core goals of semiconductor cleaning are:

• Effective particle removal
• Immediate removal of particles from the cleaning area
• Prevention of reattachment or cross-contamination

This is completely different from the industrial cleaning concept of simply making the surface look clean.

Why Is Ultrasonic Intensity Alone Not Enough?

Ultrasonic cavitation can shake particles away from the surface, but if the liquid flow inside the tank is insufficient, common problems may include:

• Particles floating inside the tank
• Particles circulating around the workpiece
• Particles reattaching to the surface after cleaning

In this situation, even increasing ultrasonic power only causes repeated particle suspension and reattachment, rather than truly improving cleaning quality.

The Role of Flow Field in Semiconductor Cleaning

A stable and uniform flow field can provide the following functions:

• Immediately carry away detached particles
• Reduce the residence time of particles inside the tank
• Prevent local concentration buildup
• Improve overall cleaning consistency

Therefore, semiconductor cleaning systems are usually equipped with circulation pumps, flow guide designs, and multi-point inlet and outlet configurations.

Excessive Cavitation May Increase Risk Instead

In industrial cleaning, the criteria for evaluating cleaning performance usually include:

• Whether the surface is free of oil contamination
• Whether it affects subsequent assembly or coating
• Whether the appearance meets customer requirements

However, in the semiconductor industry, the cleaning goal is no longer just to make the surface “look clean.” It must meet the following conditions:

• No nanoscale particles remaining on the surface
• No metal ion contamination introduced
• No damage to microstructures
• No risk to the next process step

Collaborative Design of Flow Field, Filtration, and Circulation

High-end semiconductor cleaning equipment is usually equipped with:

• Stable circulation flow
• Multi-stage filtration system
• Directional flow field design

This type of system ensures that contaminants, once removed, do not return to the cleaning area but are effectively carried away.

The key to semiconductor cleaning is not how strong the ultrasonic power is, but whether contaminants can be stably and effectively removed from the cleaning area.
Compared with simply pursuing higher cavitation intensity, a stable flow field, proper circulation, and well-designed filtration are the true core factors for ensuring cleaning consistency and process yield.
Only by starting from the perspective of particle control can the design logic of semiconductor cleaning systems be truly understood.
YONG JI Enterprise can integrate ultrasonic cleaning, flow field design, and circulation systems according to different process requirements, creating high-end cleaning systems that balance cleaning performance and process stability.