The post-etch residual polymer removal process cleans polymers from the surface of wafers. This is done in the spray solvent tool, where a commonly used post-etchant chemical, EKC®, is fed to.
It is very important to keep the EKC® solution in tight specification as too much water in the solution risks corroding the system, and too little water in solution does not efficiently remove the polymers. Vaisala K-PATENTS® Semicon Refractometer offers 2 different control strategies either to automate chemical refilling or automate spiking after each wafer run, and warrant safe wafer production.
The semicon refractometer can also alert the potential EKC® traces in IPA before IPA gets contaminated with EKC® in the following IPA/dry process.
Fabs can achieve clear benefits using a semicon refractometer:
Vaisala’s application note explains how a semicon refractometer can improve process with recommended installation points for best performance.
EKC® is a registered trademark of E. I. du Pont de Nemours and Company.
Download the application note (PDF) by filling the form.
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