We will present software tools for analyzing sensor output to optimize wet bench processes. Whether cleaning, stripping, polishing or etching, the dynamics and properties of the working fluid is critical to every step in wafer fabrication. The corrosive fluids and slurries used in wafer fabrication can often be a challenge to pump and regulate, making preventive maintenance of pumps, valves and filters critical. This should be done with the minimum of worker contact for safety, cleanliness, and to reduce costs. A new generation of smart, digital sensors are now available to make this task easier. We will focus on external flow and temperature sensors; and the best practices for correlating the data into continuous improvement programs, COPY EXACT!, and preventive maintenance protocols. Since the new generation of external sensors use ultrasound and IR radiation, they have no mechanical transients. This provides an ability to view the rapid transient behavior of the process solution. These statistics can be used to check for wear in the pumps, loss of prime, and thermal homogeneity. The logging functions of the sensor transmitters hold long term data without using up inputs or requiring new system software. We will work through trouble shooting a bellows pump and identifying the problem component using this data. We will evaluate the functioning of a small wet bench system being used to measure fluid properties of various semiconductor fluids, and show how properties other than just flow and temperature can used to improve process performance.
