Takhee Lee

Abstract In recent years, organic resistive memory devices in which active organic materials possess at least two stable resistance states have been extensively investigated for their promising memory potential. From the perspective of device fabrication, their advantages include simple device structures, low fabrication costs, and printability. Furthermore, their exceptional electrical performances such as a nondestructive reading process, nonvolatility, a high ON/OFF ratio, and a fast switchin

Graphene is a promising next-generation conducting material with the potential to replace traditional electrode materials such as indium tin oxide in electrical and optical devices. It combines several advantageous characteristics including low sheet resistance, high optical transparency and excellent mechanical properties. Recent research has coincided with increased interest in the application of graphene as an electrode material in transistors, light-emitting diodes, solar cells and flexible

A mechanically controllable break junction (MCBJ) represents a fundamental technique for the investigation of molecular electronic junctions, especially for the study of the electronic properties of single molecules. With unique advantages, the MCBJ technique has provided substantial insight into charge transport processes in molecules. In this review, the techniques for sample fabrication, operation and the various applications of MCBJs are introduced and the history, challenges and future of M

Organic memory: Our three-dimensionally (3D) stacked 8 × 8 cross-bar array organic resistive memory devices showed non-volatile memory switching behavior, in which individual memory cells in the different layers can be independently controlled and monitored. The 3D stackable organic memory devices will enable achieving highly integrable organic memory devices and other organic-based electronics with much increased cell density. Detailed facts of importance to specialist readers are published as

One diode–one resistor (1D–1R) hybrid-type devices consisting of an inorganic Schottky diode and an organic unipolar memory show electrically rewritable switching characteristics as well as rectifying properties. The 1D–1R array architecture improves the sensing efficiency of the array memory cell, ultimately creating the possibility for high-density integrated organic memory devices without restrictions due to cross-talk between cells.

Organic nonvolatile memory devices fabricated on flexible substrates showed rewritable and nearly consistent switching characteristics, regardless of the bending circumstances. This stable memory performance with bending stress is a promising property for the practical memory devices in future flexible electronics.

Abstract We demonstrate bipolar switching of organic resistive memory devices consisting of Ag/polymer/heavily‐doped p‐type poly Si junctions in an 8 × 8 cross‐bar array structure. The bistable switching mechanism appears to be related to the formation and rupture of highly conductive paths, as shown by a direct observation of Ag metallic bridges using transmission electron microscopy and energy‐dispersive X‐ray spectroscopy. Current images of high‐ and low‐conducting states acquired by conducti

Pentacene organic field-effect transistors with multilayer graphene electrodes exhibit a lower contact resistance and lower charge-injection barrier height than those with conventional Au electrodes. This enhancement in performance is related to the favorable dipole layer formation at the graphene/pentacene interface. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made availa

Room-temperature charge transport is investigated for various-length alkanethiol self-assembled monolayers using three different characterization methods, in which lateral areas span from the nanometer to the micrometer scale. In each method, the measured current−voltage characteristics are analyzed with metal−insulator−metal tunneling models. Transport parameters are determined where possible and compared across methods, as well as to previously reported values. Advantages and limitations of ea

Recently, two-dimensional materials such as molybdenum disulfide (MoS2) have been extensively studied as channel materials for field effect transistors (FETs) because MoS2 has outstanding electrical properties such as a low subthreshold swing value, a high on/off ratio, and good carrier mobility. In this study, we characterized the electrical and photo-responsive properties of MoS2 FET when stacking a p-type organic copper phthalocyanine (CuPc) layer on the MoS2 surface. We observed that the thr

1T–1R hybrid-type devices consisting of a silicon transistor and a resistive polymer memory as nonvolatile memory cell elements are demonstrated. Our results show that the operation of the 1T–1R device can be controlled by the resistance states of the polymer memory device. Written or erased data in the 1T–1R devices was maintained for more than 104 s.

Electron tunneling through self-assembled monolayers (SAMs) of alkanethiols was investigated using nanometer scale devices that allow temperature-dependent current-voltage, I(V, T), measurements. The I(V, T) measurement results show, for the first time, temperature-independent electron transport characteristics, proving direct tunneling as the transport mechanism in alkanethiol SAMs. The measured tunneling currents can be fitted with theoretical calculations using the modified rectangular barrie

Molecular junctions are building blocks for constructing future nanoelectronic devices that enable the investigation of a broad range of electronic transport properties within nanoscale regions. Crossing both the nanoscopic and mesoscopic length scales, plasmonics lies at the intersection of the macroscopic photonics and nanoelectronics, owing to their capability of confining light to dimensions far below the diffraction limit. Research activities on plasmonic phenomena in molecular electronics