Clean Pad Implementation Results – Extended Test Lifetime & Improved First Yield

Why Use Clean Pad?

During long-term testing, pin tips are prone to contamination such as tin adhesion or carbon buildup, which may trigger eutectic reactions and result in a decline in first yield.

In this case, a CST socket was selected as the Clean Pad implementation target. Through continuous testing, we compared first yield and the effect of Touchdown count on pin performance before and after Clean Pad adoption.

Before Using Clean Pad:

• After approximately 64K touchdowns, offline cleaning was required every 15K–30K touchdowns.
• After exceeding 200K touchdowns, test performance significantly degraded, and pins could no longer be used—complete pin replacement was required.
• Before reaching 230K touchdowns, offline pin cleaning was conducted seven times due to low yield.
• Pin tips were visibly worn and dulled.

After Implementing Clean Pad:

• Prior to 230K touchdowns, all cleanings were performed automatically after high-temperature testing, with no offline cleaning required due to low yield.
• Offline cleaning only began after 235K touchdowns, triggered by elevated Ron resistance.
• Before reaching 300K touchdowns, cleaning due to low yield occurred only three times
• At 297K touchdowns, the pins remained in good condition, with no noticeable blunting observed.

Conclusion：

The implementation of Clean Pad has been highly recognized by the customer. Based on actual test data, the current pin lifespan has increased by over 70K touchdowns and continues to improve. Yield retention remains stable, indicating a significant extension in pin testing life and a noticeable reduction in contact failures.

Additionally, the number of offline cleaning sessions has been greatly reduced.
For customers focusing on automated testing, mass production, and enhanced test efficiency, Clean Pad proves to be a reliable and valuable auxiliary solution.