Generic behavior of ultrastability and anisotropic molecular packing in co-deposited organic semiconductor glass mixtures
arXiv:2607.08889 · doi:10.1021/acs.chemmater.3c02935
Abstract
Vapor-deposited glass mixtures of organic semiconductors commonly serve as active layers in organic electronic devices, whose lifetime and performance are strongly influenced by the stability and structure of these mixed glasses. Here, we study the stability and anisotropic molecular packing of six co-deposited organic semiconductor glass mixtures with 50:50 weight ratio, by differential scanning calorimetry and spectroscopic ellipsometry. We find that all six binary systems exhibit high kinetic stability and significantly reduced enthalpy relative to the corresponding liquid-cooled glassy mixtures (ultrastable behavior), even for systems where the glass transition temperatures of the components differ by more than 90 K. Furthermore, we demonstrate that the birefringence of a co-deposited glass mixture, a measure of its anisotropic packing, can be predicted from the birefringence of glasses of the two pure components. These results for stability and structure are expected to be applicable to other co-deposited organic semiconductor glass mixtures, so long as the two components mix well in the glass and individually can form ultrastable glasses. Therefore, our findings are significant for designing novel electronic devices with enhanced device lifetime and increased operational efficiency.
5 figures, 27 pages, 51 references, Supplemental Information (6 figures)
References in corpus (5)
- Two-Level Systems and Boson Peak Remain Stable in 110-Million-Year-Old Amber Glass
- Highly Stable Glasses of cis-Decalin and cis/trans-Decalin Mixtures
- Controlling Spontaneous Orientation Polarization in Organic Semiconductors -- The Case of Phosphine Oxides
- Stable Glasses of Organic Semiconductor Resist Crystallization
- Surface Equilibration Mechanism Controls the Stability of a Model Co-deposited Glass Mixture of Organic Semiconductors