A generic method for the reverse processing of dry photoresist is proposed. The technique is based on the lamination of pre-patterned polymeric structures on the pre-existing devices. The concept is illustrated with the encapsulation at the foil level of gas sensors made on plastic foil. This polymeric-based technique can be either applied on plastic foils but also on conventional substrates such as silicon or glass. It can be used when standard packaging techniques might not be suitable or when they can represent a significant cost. Using the lamination of a foil, the low-temperature and dry process presented here is compatible with large scale fabrication techniques, such as roll-to-roll processing, and aims at reducing the global fabrication cost of sensing devices made on plastic foil. (C) 2009 Published by Elsevier Ltd.