Researchers have found that fine-tuning the composition of microscopic layers could lead to significant improvements in device performance. The University of Ottawa team found that small changes to the materials and structure of electronic devices significantly improve their efficiency and sustainability.
Because these devices rely on carefully arranged layers to conduct electricity, adjusting their composition at the microscopic level can be crucial to developing electronics that use less power and support more sustainable designs. By changing these layers, researchers hope to significantly improve the function of devices – especially smaller, wearable and biodegradable devices.
Improvements can even open up new applications for electronics
Benoit Lessard’s research group at the University of Ottawa is researching various materials that can serve as the base layer for these conductive stacks, called thin-film transistors.
“It’s really important to keep the bottom layer in mind when you put the next layer on top, because it’s going to affect how the next layer organizes and how those molecules are aligned,” Lessard said.
The team emphasized that the improvements could even open up new uses for electronics, such as reducing harm from street drugs. Lessard’s group is developing sensors that use electrochemical reactions to determine not only what substances are present in a sample, but also their quantity.
Current tests for drugs like fentanyl are “useful for saying yes or no,” Lessard said. But knowing exactly how much fentanyl is present in a sample would be extremely helpful for both drug users and the medical staff treating them.
Electronic devices often rely on thin film transistors
Electronic devices often rely on thin film transistors, which control the movement of electrical signals and are widely used in display technology and other electronic applications. Their performance depends not only on the materials used, but also on how those materials are arranged at the molecular level.
The layer beneath the active material plays a particularly important role. Its chemical composition and physical properties can influence how molecules in the top layer align and organize. Even small changes in this arrangement can affect how efficiently electrical charges move through a device and how much voltage is required for it to function.
Researchers studied n-type organic thin film transistors (OTFTs) based on bis(pentafluorophenoxy) silicon phthalocyanine (F10SiPc) fabricated on a series of methacrylate-based polymer dielectrics containing polymerized ionic liquid (PIL) units.
“Using grazing-incidence synchrotron wide-angle X-ray scattering analysis, atomic force microscopy, and electrical characterization, we show that tuning the PIL content provides control over F10SiPc orientation on the substrate,” the researchers said in the study.
“Increasing the PIL content from 12% to 65% enables OTFT operation at voltages as low as 0.9 V, with an ion/Ioff ratio of 104 and a transconductance of up to 1850 nS. This work emphasizes the importance of the dielectric/semiconductor interface for low VT OTFTs using PILs and F10SiPc.”
