Eintrag in der Universitätsbibliographie der TU Chemnitz
Volltext zugänglich unter
URN: urn:nbn:de:bsz:ch1-qucosa2-805939
Li, Tianming
Schmidt, Oliver G. (Prof. Dr.) ; Zhu, Feng (Prof. Dr.) (Gutachter)
Integrated Organic and Hybrid Nanodevices Based on Rolled-up Nanomembrane Contacts
Kurzfassung in englisch
The physical limitations of miniaturization of the traditional silicon-based electronic devices have motivated growing interest in molecular electronics due to its promising potential in transcending Moore's Law. Since the concept of molecular rectifier was first proposed by Ratner and Aviram in 1974, a lot of efforts have been devoted to realizing nondestructive electrical contacts to the individual or ensemble molecules, such as liquid metal contact, break junctions, cross wire junctions, etc. Among them, rolled-up nanotechnology is compatible with the conventional photolithography processes and can provide an efficient strategy to fabricate fully integrated functional molecular devices on a chip via an array of damage-free soft contacts. This nanotechnology takes an important step towards implementing the miniaturization of molecular devices and promotes the development of molecular electronics.In this doctoral thesis, rolled-up nanotechnology is employed to develop functional molecular devices on chips. Enabled by these rolled-up soft contacts, fully integrated molecular rectifiers based on ultrathin molecular heterojunctions are developed for the first time, and they are able to convert alternating current to direct current with frequencies up to 10 MHz. This is also the first time that a nanoscale organic rectifier with an operating frequency exceeding 1 MHz has been fabricated. The remarkable unidirectional current behavior of the molecular devices mainly originates from the intrinsically different surfaces of bottom planar and top microtubular gold electrodes. While the excellent high-frequency response is guaranteed by the charge accumulation in the phthalocyanine molecular heterojunction, which not only improves the charge injection but also increases the carrier density.
Then this rolled-up nanotechnology is further employed to explore multi-functional molecular devices. In this thesis, fully integrated process-programmable molecular devices are achieved for the first time, which can switch between photomultiplication photodiodes and bipolar memristors. The transition depends on the release of mobile ions initially stored in the bottom polymeric electrode and can be controlled by modulating the local electric field at the interface between the ultrathin molecular layer and the bottom electrode. Photogenerated-carrier trapping at a low interfacial electric field leads to photomultiplication with an ultrahigh external quantum efficiency (up to 104%). In contrast, mobile-ion polarization triggered by a high interfacial electric field results in ferroelectric-like memristive behaviour with both remarkable resistive on/off ratios and rectification ratios. The combination of the “soft-contact” enabled by rolled-up nanotechnology and the “ion reservoir” provided by the polymeric electrode opens up a novel strategy for integrating multi-functional molecular devices based on the synergistic electronic-ionic reaction to various stimuli.
| Universität: | Technische Universität Chemnitz | |
| Institut: | Professur Materialsysteme der Nanoelektronik | |
| Fakultät: | Fakultät für Naturwissenschaften | |
| Dokumentart: | Dissertation | |
| Betreuer: | Schmidt, Oliver G. (Prof. Dr.) | |
| SWD-Schlagwörter: | Molekularelektronik | |
| Freie Schlagwörter (Englisch): | molecular electronics , rolled-up soft contacts , molecular rectifier , photomultiplication photodiode , bipolar memristor | |
| DDC-Sachgruppe: | Technik, Medizin, angewandte Wissenschaften | |
| Sprache: | englisch | |
| Tag der mündlichen Prüfung | 29.08.2022 |
