Method for batch manufacturing sensor units

This invention relates to a method for manufacturing sensors, with particular, but by no means exclusive, reference to gas sensors comprising conducting polymers (CPs). There is disclosed a method for manufacturing a batch of sensors including providing a substrate which has a plurality of conductive tracks formed thereon; electrochemically depositing a first active sensing material layer over the substrate and the conductive tracks in a process in which the conductive tracks are part of a single electrical circuit; removing deposited active sensing material from predetermined portions of the substrate: and sub-dividing the substrate to produce a plurality of sensor units.