Metal-Oxide Thin Film Transistors Solution-Processed at Low Temperature for Electronic and Sensing

Following the ever-growing market demand for new forms of electronics, flexible and printed electronics is gaining in maturity and several products are reaching the market in the field of display, lightning, photovoltaic, and more slowly electronic circuits and sensors. Recently, the research on thin film transistors has been focusing on metal-oxide semiconductors which can offer superior electrical characteristics in comparison to organic semiconductors.

The FOXIP project aims to solve one key challenge of printed electronics: to demonstrate a metal-oxide based thin film transistor (TFT) printed on temperature sensitive substrates such (bio)polymers and paper.  EPFL-LMTS is involved in several challenging aspects of the project. Planarization and functionalization of the substrate, through use of coatings or patterning of the surface will be performed. High importance will be given to the development of innovative solutions for each element of the TFT: dielectric layer, metal-oxide semiconductor and conductive electrodes, to achieve their low temperature processing (< 200°C). In this context, promising chemical processes, such as deep-UV assisted sol-gel  synthesis and photonic sintering, have been successfully investigated.

We are currently focusing on the additive manufacturing of metal-oxide transistors on cellulosic and biopolymeric substrates. These devices will be applied as sensors, using an electrolyte gated configuration, and as electronic devices using a standard bottom gate configuration. Finally, we are demonstrating their use as disposable and biocompatible biosensors and as switches in flexible haptic displays developed in the laboratory.

Project website:

Project partners:

  • Laboratory for Thin Films and Photovoltaics, Empa
  • Laboratory for Functional Polymers, Empa
  • Polymer Nanotechnology Group, PSI

Project funding: The program of the Strategic Focus Area (SFA) Advanced Manufacturing

Scientific publications:

A. Mancinelli, S. Bolat, J. Kim, Y. Romanyuk, D. Briand, Deep-UV-enhanced Approach for Low Temperature Solution Processing of IZO Transistors with High-k AlOx/YAlOx Dielectric, ACS Appl. Electron. Mater. 2(10) (2020) 3141–3151.

S. Bolat, G. Torres-Sevilla, A. Mancinelli, E. Gilshtein, J. Sastre-Pellicer, D. Bachmann, A. Cabas Vidani, I. Shorubalko, D. Briand, A. Tiwari, Y. Romanyuk, Synaptic transistors with aluminum oxide dielectrics enabling full audio frequency range signal processing, Scientific Reports (2020) 10:16664.

Contact: Dr. Danick Briand