We report a Kelvin-probe method to investigate the lateral charge-transport properties of semiconductors, most notably the charge-carrier mobility. The method is based on successive charging and discharging of a pre-biased metal-insulator-semiconductor stack by an alternating voltage applied to one edge of a laterally confined semiconductor layer. The charge carriers spreading along the insulator-semiconductor interface are directly measured by a Kelvin-probe, following the time evolution of the surface potential. A model is presented, describing the device response for arbitrary applied biases allowing the extraction of the lateral charge-carrier mobility from experimentally measured surface potentials. The method is tested using the organic semiconductor poly(3-hexylthiophene), and the extracted mobilities are validated through current voltage measurements on respective field-effect transistors. Our widely applicable approach enables robust measurements of the lateral charge-carrier mobility in semiconductors with weak impact from the utilized contact materials.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1063/1.5002629 | DOI Listing |
J Am Chem Soc
January 2025
Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University and Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China.
High mobility emissive organic semiconductors (HMEOSCs) are a kind of unique semiconducting material that simultaneously integrates high charge carrier mobility and strong emission features, which are not only crucial for overcoming the performance bottlenecks of current organic optoelectronic devices but also important for constructing high-density integrated devices/circuits for potential smart display technologies and electrically pumped organic lasers. However, the development of HMEOSCs is facing great challenges due to the mutually exclusive requirements of molecular structures and packing modes between high charge carrier mobility and strong solid-state emission. Encouragingly, considerable advances on HMEOSCs have been made with continuous efforts, and the successful integration of these two properties within individual organic semiconductors currently presents a promising research direction in organic electronics.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Oxford University: University of Oxford, Department of Chemistry, UNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELAND.
Organic semiconducting polymers play a pivotal role in the development of field-effect transistors (OFETs) and organic light-emitting diodes (OLEDs), owing to their cost-effectiveness, structural versatility, and solution processability. However, achieving polymers with both high charge carrier mobility (μ) and photoluminescence (PL) quantum yield (Φ) remains a challenge. In this work, we present the design and synthesis of a novel donor-acceptor π-conjugated polymer, TTIF-BT, featuring a di-Thioeno[3,2-b] ThioenoIndeno[1,2-b] Fluorene (TTIF) backbone as the donor component.
View Article and Find Full Text PDFNat Commun
January 2025
Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, Dresden, Germany.
Charge-carrier compensation in topological semimetals amplifies the Nernst signal and simultaneously degrades the Seebeck coefficient. In this study, we report the simultaneous achievement of both a large Nernst signal and an unsaturating magneto-Seebeck coefficient in a topological nodal-line semimetal TaAs single crystal. The unique dual-high transverse and longitudinal thermopowers are attributed to multipocket synergy effects: the combination of a strong phonon-drag effect and the two overlapping highly dispersive conduction and valence bands with electron-hole compensation and high mobility, promising a large Nernst effect; the third Dirac band causes a large magneto-Seebeck effect.
View Article and Find Full Text PDFInorg Chem
January 2025
Department of Chemistry, National Institute of Technology, Rourkela 769008, Odisha, India.
Design of hierarchical hollow nanoheterostructure materials through interfacial and defect engineering is an innovative approach for achieving optimal charge separation dynamics and photon harvesting efficiency. Herein, we have described a facile technique to fabricate hollow MOF-derived C, N-doped-CoO (C, N-CoO) dodecahedral particles enwrapped with MgInS nanosheets for enhanced N reduction performance. ZIF-67 was initially used as a sacrificial template to prepare hollow C, N-CoO using a carbonization route followed by low-temperature calcination treatment.
View Article and Find Full Text PDFMater Horiz
December 2024
Walter Schottky Institute, Technical University of Munich, 85748 Garching, Germany.
Semiconducting ternary nitrides are a promising class of materials that have received increasing attention in recent years, but often show high free electron concentrations due to the low defect formation energies of nitrogen vacancies and substitutional oxygen, leading to degenerate n-type doping. To achieve non-degenerate behavior, we now investigate a family of amorphous calcium-zinc nitride (Ca-Zn-N) thin films. By adjusting the metal cation ratios, we demonstrate band gap tunability between 1.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!