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US 7,732,225 B2Granted
Method for measuring contamination in liquids at PPQ levels
AssigneeTexas Instruments Incorporated
InventorsJeffrey Allen Hanson, Lee M. Loewenstein, Monte Allan Douglas
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Abstract
A method of manufacturing a semiconductor device includes placing a sample of a liquid chemical containing a contaminant on a substantially impurity-free surface of a substrate. The liquid chemical is evaporated, leaving the contaminant on the surface. The contaminant is concentrated in a scanning solution, which is then evaporated to form a residue. A concentration of the contaminant in the residue is determined.
Claims6
A method for measuring contamination of ultrapure water (UPW), the method comprising:
- cleaning a silicon wafer;
- exposing the silicon wafer to hydrogen fluoride vapor;
- placing a volume of the UPW onto the silicon wafer;
- drying the UPW on the silicon wafer;
- and
- measuring metallic contaminants remaining on the silicon wafer from the UPW.
3 more elements
Dependencies are inferred from the claim text.