Wafer cleaning issues at the wet process
Current situation
Defects were found on the surface of the wafer after washing with the chemistry and rinsing with water.
Disadvantages
- The wafer contaminated with defects cannot be sold to the customer. The defective wafers will be scrapped.
- The process strongly depends on chemicals. Small change, even within spec limits, causes contamination of the wafers and a drop in the yield.
- The process and products are at high risk of failure due to even insignificant changes.
Ideal final result
Stable yield after using the chemistry from different vendors with no cost increase.
Gaps
Certain type of chemistry creates and leave defects on the silicon wafer during wet cleaning
Problem statement
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