Presenter：Prof. Stefan Mannsfeld (Technische Universität Dresden, Germany)
Topic：Engineering of Polymer Films for Optoelectronic Applications
Time：2026.10.10 13:30 pm
Location：909-B
Abstract:
The potential of organic field-effect transistors (OFETs) in sensing applications is considerable due to their multi-parametric electrical response and high sensitivity to diverse environmental changes, including light, chemicals, and temperature. Their use in optoelectronics, as organic phototransistors (OPTs), has attracted significant interest across disciplines like bioimaging, health monitoring, and medical applications. Current research focuses on developing multibit OPT memory devices with large storage-level differences via different floating gates or electrets, alongside achieving high sensitivity. As in a solar cell, separating light-induced electron-hole pairs is critical to an OPT’s net sensitivity, making photovoltaically active multilayer junctions a key research direction.
In the first part of this presentation, our recent work on these topics is highlighted, employing photoactive small molecule-polymer junctions which either contain a dedicated charge-trapping layer or use the polymer for that purpose. This part also presents a new concept to define an external quantum efficiency for such organic charge-trapping devices.
The second part introduces a recent approach to achieve fully solution-coated photoactive co-planar polymer-polymer interfaces. This is achieved by what is dubbed "Thermal Physical Crosslinking" (TPC), rendering common polymer layers solvent-resistant without the use of a chemical crosslinker. Besides opening up exciting avenues for general polymer multilayer devices, this effect has immediate utility to achieve polymer-polymer OPT devices.
Biography：
Prof. Dr. Stefan C. B. Mannsfeld is a Full Professor of Organic Devices at the Department of Electrical Engineering and Information Technology and the Center for Advancing Electronics Dresden (cfaed) at the Technical University of Dresden, Germany. He earned his M.Sc. and Ph.D. in Physics from TU Dresden, completing his doctorate in 2004. Prior to his current appointment in 2014, he spent nearly a decade in the United States at Stanford University. This included postdoctoral research as a DFG fellow in the Department of Chemical Engineering with Prof. Zhenan Bao, and subsequent work as a Staff Scientist at the Stanford Linear Accelerator Center (SLAC) National Laboratory. His research focuses on thin-film electronics, specifically the development and optimization of solution-coated organic and metal oxide electronic devices.
Contact: Gao Xu, Wang Suidong