Abstract
To date, measuring the carrier mobility in semiconductor films, especially for the amorphous organic small-molecule films, is still a big challenge. Here, we demonstrate that transient electroluminescence (TrEL) spectroscopy with quantum-dot light-emitting diodes as the platform is a feasible and reliable method to evaluate the carrier mobility of such amorphous films. The position of the exciton formation zone is precisely determined and controlled by employing a quantum dot monolayer as the emissive layer. The electrical field intensity across the organic layer is evaluated through the charge density at the electrode calculated by the transient current. Then, the charge carrier mobility is obtained by combining the electroluminescence (EL) delay time and the thickness of the organic layer. Additionally, we demonstrate that the large roughness of the organic layer leads to serious charge accumulation and, hence, a high localized electrical field, which provides preferred charge injection paths, reducing the EL delay time and underestimating the EL delay time. Therefore, a thick organic film is the prerequisite for a reliable measurement of charge carrier mobility, which can circumvent the negative effect of film roughness.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.