Anorganische Dünnschichtelektronik
Der LEB beteiligt sich im Rahmen vieler unterschiedlicher Forschungskooperationen an der Entwicklung von gedruckten Bauelementen auf Basis von anorganischen Dünnschichten aus Nanopartikel-Dispersionen oder gelösten molekularen Vorstufen. Für zahlreiche Anwendungen wie z.B. die elektronische Etikettierung, oder großflächig verteilte Sensorik für Internet-of-Things- und Industrie 4.0-Anwendungen sind kostengünstige Alternativen zur Standard-Silicium-Technologie mit teilweise entspannten Anforderungen an die elektrischen Parameter gefragt. Gedruckte Bauelemente basierend auf halbleitenden Polymeren besitzen den Nachteil einer geringen Langzeitstabilität aufgrund von UV-Licht-, Feuchteempfindlichkeit sowie elektrischer Degradation, so dass sich die Forschungsaktivitäten am LEB auf den Einsatz von anorganischen Halbleitern wie Silicium, Germanium und Metalloxiden fokussieren. Als Brückentechnologie zur Umsetzung gedruckter elektronischer Systeme setzt der LEB zudem konventionelle Vakuumprozesstechniken zur Realisierung von Dünnschichtbauelementen ein, beispielsweise die Kathodenzerstäubung.
Projects:
Thin-film transistors (TFTs) are mainly used in flat panel displays as switches for selecting pixels. In TFTs the electric conductivity of a semiconductor layer placed between two contacts, called source and drain, is influenced by a third contact, the gate. The current can thus be varied over several orders of magnitude. The TFT is switched off when the current flow is negligibly small (for example a few pikoampere) and switched on when the current is much larger (for example, several microampers). Switching over always takes some time (fractions of seconds). If source and drain are closer together (the so-called channel is smaller), this time is reduced and the TFT switches faster. In state of the art thin-film-transistors (TFTs), both source and drain electrodes are placed at the same side or interface of the semiconductor layer. Positioning the two contacts on opposite interfaces of the semiconductor in an Alternating Contact TFT (ACTFT) enables new degrees of freedom for device design, optimization, and operation. The ability to enable short channel lengths is explored for application in radio frequency (RF) circuitry in this project.Two research groups of FAU Erlangen Nuremberg being experts in device technology (Chair of Electron Devices) and RF circuits engineering (Institute of Electronics Engineering) join forces to cover the integrated development of ACTFTs towards basic RF building blocks and systems based on flexible metal oxide TFTs. Studies on device physics, RF behavior, and novel circuit concepts will open perspectives for the use of large area, thin, and bendable TFT technologies in future industrial, consumer, and wearable electronics.
The deposition of silicon thin films from dissolved and formulated polysilane precursors and the integration of the layers into electronic applications are the main goals of the proposed project.In comparison to other inorganic materials from liquid-phase deposition, silicon is supposed to offer advantages in terms of fundamental device parameters (e.g. carrier mobilities), stability and reliability, as well as controllability of material parameters (e.g. doping).The scientific challenges of the…
The chair of electron devices develops electronic thin films from nanoparticles. Whereas particles can be synthesized in excellent materials quality at high temperatures, the low-temperature deposition of thin films allows for the integration with sensitive substrates as paper or polymer foils. Thus, novel bendable and large-area devices like displays or solar cells will be enabled in future.
The most important task with thin-film formation from nanoparticles is the control of electronic properties and the encapsulation against environmental impacts which both had been investigated in a prior phase of the project. In the current period, application-related issues like the influence of geometry on the current-voltage characteristics and the integration of devices into circuits are adressed.
Project A6 combines the findings from the first funding period, which investigated the transport properties of metallic nanowires as well as inorganic nanoparticles as a function of microstructure and microstructure with c-AFM and electron microscopy methods. The follow-up project will address the electrical and optical properties of nanoparticle-filled nanowire composites. The focus of the investigations is on the microscopic understanding of the charge carrier transport between the semiconducting…
Dieses Projekt zur Entwicklung von druckbarer Elektronik wird im Rahmen des Graduiertenkollegs "Disperse Systems" durchgeführt und von der DFG sowie der Evonik Industries AG (vormals Degussa) unterstützt.
Im Gegensatz zu Bauelementen für Computerchips, Steuerungen und Ähnlichem, wo die Anforderungen im Hinblick auf Dimensionierung und Schaltgeschwindigkeiten stetig steigen, gibt es auch Anwendungen, wie z.B. die elektronische Etikettierung, in denen nicht die…