
Sensor channels measure the impedance of cleaning fluids in closed-loop process that stops cleaning when done rather than wasting resources. Source: SRC
Here is what EETimes says about putting cleaning sensors of wafers: Energy efficient semiconductor fabrication techniques have largely eluded designers of wafer cleaning processes, which still depend on open-loop recipes that waste energy and water. By closing the loop with on-wafer sensors, the Semiconductor Research Corp. (SRC, Research Triangle, N.C.) said it has developed a technology that saves as much as 80 percent of the water and energy required by traditional open-loop cleaning.
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