1. A method of formulating clean, rinse and dry processes for the manufacture of production wafers including micro devices having micro features, comprising: a) providing an electro-chemical residue sensor (ECRS) comprising a micro feature formed in or on a dielectric film and first and second conductive electrodes adapted to receive an ac signal to measure the impedance of the micro feature, said micro feature being representative of the device micro features on the production wafer; b) measuring the impedance of the ECRS micro feature as the ECRS is subjected to at least one of the clean, rinse and dry processes; and c) using the measured impedance to determine a production process condition for the at least one process.