A new approach has been found by an undergraduate student from the University of Surrey to subdue hot-carrier impact that has plagued devices using thin-film transistor architecture, like solar panels and smartwatches.
During her final-year project, Lea Motte investigated a new device, the multimodal transistor, which is a substitute to traditional thin-film transistors, invented and designed by PhD candidate Eva Bestelink and supervisor Dr. Radu Sporea at Surrey University.
Lea applied a defining feature of multimodal transistors, the isolation of controls for initiating electrons into the device and enabling them to move through the transistor. Lea used computer simulations and found that selecting the right voltage to apply to the transport control region could help prevent undesirable hot-carrier effects. It also guarantees that the current flowing via the transistor stays constant in an extensive range of operating conditions.
Eva Bestelink, a PhD student, systematically analyzes Lea’s breakthrough of the strange behavior in multimodal transistors by verifying it with measurements in microcrystalline silicon transistors and executing comprehensive device simulations to comprehend the device physics that forms the basis of its unique potential.
The study has been reported in the Advanced Electronic Materials journal.
This breakthrough implies that future technologies using multimodal transistors could turn out to be more power-efficient. Furthermore, it could result in high-performance amplifiers, which are vital for quantifying signals from biological and environmental sensors.
We now have a better understanding of what the multimodal transistor can offer when made with materials that cause numerous challenges to regular devices. For circuit designers, this work offers insight into how to operate the device for optimum performance. In the long term, the multimodal transistor offers an alternative for emerging high-performance materials, where traditional solutions are no longer applicable.
Eva Bestelink, Study Lead Author, University of Surrey
According to Dr. Radu Sporea, Senior Lecturer in Semiconductor Devices at the University of Surrey and supervisor of both Lea and Eva’s projects, “This new understanding adds to the set of features of the highly versatile multimodal transistor. It also shows the value of multidisciplinary collaboration through close interactions with one of our many partner institutions in Rennes, France.”
Finally, it demonstrates again that in our team, everyone’s contribution can lead to important developments, even as undergraduates. This is why, at Surrey, we encourage our students to explore widely and to challenge the boundaries of their assigned projects.
Dr. Radu Sporea, Senior Lecturer in Semiconductor Devices, University of Surrey
Bestelink, E., et al. (2021) Suppression of Hot-Carrier Effects Facilitated by the Multimodal Thin-Film Transistor Architecture. Advanced Electronic Materials. doi.org/10.1002/aelm.202100533.