Printed pressure sensor matrix with organic field-effect transistors

The paper presents the construction and fabrication method of a pressure sensor matrix with organic field-effect transistors. The sensor structure consists of a matrix of air-gap transistors which is realized by roll-to-roll processing and laminating methods. High aspect ratio spacer structures are made by inkjet printing.The sensor cell transistor senses the applied force on the top substrate due to changes in the air-gap dimension. The sensor matrix has measurement range of 0.4 kPa−1-4.4 kPa−1, sensitivity 0.4 ± 0.1 kPa−1 and time response better than 300 ms. The structure is scalable and it has a sensitivity comparable to state of the art pressure sensor matrices that use organic field-effect transistors. Its fabrication process, however, includes standard, low cost mass production steps of printed electronics and it can be transferred to a roll-to-roll process.