Potentiostat for a vacuum sputter coater
A potentiostat built to replace the broken Pirani gauge on a sputter coater, using a PT100 in a Wheatstone bridge and Keithley ICs for I–V measurement.
The Pirani gauge on the lab’s vacuum sputter coater broke, so I built a potentiostat to take its place.
A PT100 temperature sensor sits inside the vacuum environment as one arm of a Wheatstone bridge, and Keithley ICs handle the I–V measurements. A Pirani gauge works by measuring how quickly a heated element loses heat to the surrounding gas, so with the right sensing electronics the same physics can be read out through a different instrument.