It combines input from the HF monitor and operator input specifications to calculate and then provide in real-time a recommendation for the amount of HF or H2O to add to the bath. It adjusts and maintains the appropriate ratio of chemicals to achieve accurate etching of the wafers. This real-time process feedback can result in the reduction of, or even elimination of, process monitor wafers, which translates into considerable savings in operating expenses. Real-time monitoring makes closed loop solutions possible.
Valid for HF concentration ranges of .1 to 5.0 weight percent
Valid for HF bath temperatures from 14 to 34 degrees Celsius
Accuracy of estimated SiO2 etch rate is +/- 2% with proper etch adjustment factor 110 AC
Connection to the HF monitor with a 9 pin RS232 cable