CORRELATION BETWEEN CONDUCTIVITY AND PH MEASUREMENTS FOR KOH TEXTURING SOLUTIONS AND ADDITIVES

摘要

The variability of an etchant concentration in an immersion processes for treatment of semiconductor devices can be significantly lowered by continuously measuring the conductivity of an etchant solution and comparing against predetermined thresholds. The etchant concentration can be maintained by a feed and bleed process based on conductivity measurements of the etchant solution and the conductivity measurements being correlated with premeasured pH values of an etchant solution.