Conductive Coordination Networks Compounds for Microelectronic Applications
Consortium: | Dr. Engelbert Redel, Karlsruhe Karlsruher Institut für Technologie Institut für Funktionelle Grenzflächen (IFG) |
Prof. Gunther Wittstock, Oldenburg Carl von Ossietzky Universität Oldenburg Arbeitsgruppe für Physikalische Chemie (Wittstock) | |
Project: | Conductive Coordination Networks Compounds for Microelectronic Applications |
Abstract: | This project will focus on the development and preparation of new conductive coordination network compounds (CCNCs) as thin films on conducting supports for the ultimate use as active material in microelectronic devices and applications. Current surface bound metal-organic frameworks built of transition metal cations (like Zn2+ and/or Cu+/2+) and carboxylate ligands lack the electrical conductivity required for electronic application. Polycrystalline layers of Prussian Blue (PB) are known to exhibit a mixed electronic and ionic conductivity. PB films have recently been prepared as monolithic and highly ordered crystalline thin films by liquid phase epitaxy (LPE). This achievement forms the starting point of this project from which new materials will be developed and characterized for electronic and microelectronic device application. For the functional characterization we will study the electrochemistry by thin film voltammetry linked to x-ray photoelectron spectroscopy (XPS) to determine the location, where valence changes occur, as well as the fraction of lattice constituent that undergo valence changes. This behavior will be compared to e.g. bipolar switching measurements in all-solid state CCNCs devices and to the results of theoretical calculations from cooperation partners. The possibilities will be enhanced by using unsaturated polynitrile pi-acceptor ligands instead of cyanide ligands e.g. in PB. The creation of porous CCNCs further allows the incorporation of guest molecules as well as large conformational changes of the entire CCNC molecular network upon valence changes of the constituents, e.g. by using an external bias. In addition, such ligands can also be reduced by themselves which may open another path towards switchable conductivity of CCNCs formed from them. After a thorough study of preparation routes and characterization of the conductivity and the opportunities to change the conductivity of such materials by partial oxidation or reduction we will focus on the construction of a prototypic device such as a resistive random access memory (RRAM) or metal organic field effect transistor (MOFET) that will be characterized in cooperation with external partners (NIST) with respect to their performance. |
Publications: | Z. Wang, D. Nminibapiel, P. Shrestha, J. Liu, K. P. Cheung, W. Guo, P. G. Weidler, H. Baumgart, C. Wöll, E. Redel "Resistive Switching Nanodevices based on Metal-Organic Frameworks" ChemNanoMat 2016, 2, 67-73 DOI: 10.1002/cnma.201500143 |
J. Liu, W. Zhou, S. Walheim, Z. Wang, P. Lindemann, S. Heissler, P. G. Weidler, C. Wöll, E. Redel "Electrochromic switching of monolithic Prussian blue thin film devices" Opt. Express 2015, 23, 13725-13733 DOI: 10.1364/OE.23.013725 | |
J. Liu, E. Redel, Z. Wang, V. Oberst, J. Liu, S. Wahlheim, S. Heissler, M. Bruns, H. Gliemann, C. Wöll "Multilayered Hybrid HKUST-1/ITO Photonic Crystal Devices" Chem. Mater. 2015, 27, 1991-1996 DOI: 10.1021/cm503908g | |
S. Sauter, G. Wittstock "Local Deposition and Characterisation of K2Co[Fe(CN)6] and K2Ni[Fe(CN)6] by Scanning Electrochemical Microscopy" J. Solid State Electrochem. 2001, 5, 205-211 DOI: 10.1007/s100080000137 | |
S. Sauter, G. Wittstock, R. Szargan "Localisation of electrochemical oxidation processes in nickel and cobalt hexacyanoferrates investigated by analysis of the multiplet patterns in X-ray photoelectron spectra" Phys. Chem. Chem. Phys. 2001, 3, 562-569 DOI: 10.1039/b008430l | |
P. Hosseini, G. Wittstock, I. Brand, "Infrared spectroelectrochemical analysis of potential dependent changes in cobalt hexacyanoferrate and copper hexacyanoferrate films on gold electrodes" J. Electroanal. Chem. 2018, 812, 199 DOI: 10.1016/j.jelechem.2017.12.029 |