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Functional nanoelectronic devices: single-electron transport, memristivity, and thermoelectricity in nanoscale flms using self-assembly and graphene 10.17863/CAM.38857 Astier, Hippolyte Pierre Andre Georges Ford, Christopher John Bristow This dissertation reports on several experimental projects studying electronic transport in thin-flm electronic devices. Self-assembly methods and graphene were used to realise devices contacting films of self-assembled PbS quantum dots. The devices have exhibited single-electron tunnelling with a high yield. The electrical properties of the junctions are studied individually and collectively using statistical tools to extract correlations between device geometries and electrical data. The dissertation includes discussion of the theory of relevant electronic transport including numerical simulations. Several initiated projects deriving from this work are introduced. A second device reported in this thesis is a memristive switch. Contacting thin films of Al2O3 with graphene delivered junctions which exhibit memristive behaviour with an ultrahigh on-off conductance ratio. The conduction state of the junctions is correlated with morphological changes in the devices, whereby conductive flament formation in the junction is found to lead to electrically-controllable and reversible gas encapsulation in bubbles in the structure. The device is measured electrically and topographically, and the correlation between the two aspects is studied. A discussion of memristive conduction is included with numerical simulations. A third section reports on a project studying thermoelectricity in self-assembled molecular junctions, as they show potential for improved thermoelectric efficiency for energy harvesting; this is discussed in the dissertation. Strategies to benchmark the studies are presented with relevant devices fabricated and measured. These include the development of a measurement protocol to study thermoelectricity in devices, studies of electrical coupling between various molecular structures and graphene electrodes, molecular-structure dependence of electrical and thermal conductance of junctions. Preliminary results and on-going work are discussed. University of Cambridge 2019-04-27 Thesis Doctoral Doctor of Philosophy (PhD) en I want to thank the Semiconductor Physics Group of the Cavendish Laboratory, the Semiconductor Physics Group of the Institute of Physics, the Cambridge NanoDTC, and Fitzwilliam College, Cambridge for their support. I want also to thank the collaborators acknowledged in the thesis for contributions in materials and services. https://www.repository.cam.ac.uk/handle/1810/291697 https://www.repository.cam.ac.uk/bitstreams/80efcc97-c0ea-4b5e-84eb-f1e6297e7e1b/download 4955fdf3711fc5f7c40ea05c9b762942 https://www.repository.cam.ac.uk/bitstreams/60c92fb5-3afd-4d12-8eb8-963e360cb5f9/download 87eda9de84448d1f82354d60eee3eb5f https://www.rioxx.net/licenses/all-rights-reserved/ molecular elctronics graphene devices nanoelectronics thin films self-assembly quantum dot thermoelectricity single-electron tunnelling single-electron tunneling self-assembled monolayer memristor memristivity nanoactuation semiconductor physics condensed matter physics thermoelectric energy harvesting Coulomb blockade Coulomb staircase nanocrystal