METHOD OF FORMING SELF-ASSEMBLED AND UNIFORM FULLERENE ARRAY ON SURFACE OF SUBSTRATE

本發明提供一種於基板表面生成自組裝且高度均勻之碳簇分子陣列的方法，其包括以下之步驟：(1)　提供一基板；(2)　在真空環境下將該基板加熱至約200℃至約1000℃；及(3)　提供一碳簇分子奈米粉末，並在該真空環境下藉由物理氣相沈積法將該碳簇分子奈米粉末沈積在該基板表面上，從而於該基板表面上形成自組裝且高度均勻之碳簇分子陣列。本發明亦提供一種由此製得之碳簇分子陣列嵌入式基板，其具有優異之場發射性能，可作為場發射器用於任何場發射顯示器(Field Emission Display；FED)中。最後，本發明亦提供一種由此製得之碳簇分子陣列嵌入式基板，其可替代碳化半導體材料，作為光電元件及高溫、高功率、抗高溫或高頻率電子元件之用

METHOD OF FORMING SELF-ASSEMBLED AND UNIFORM FULLERENE ARRAY ON SURFACE OF SUBSTRATE

本發明提供一種於基板表面生成自組裝且高度均勻之碳簇分子陣列的方法,其包括以下之步驟:(1)提供一基板;(2)在真空環境下將該基板加熱至約200℃至約1000℃;及(3)提供一碳簇分子奈米粉末,並在該真空環境下藉由物理氣相沈積法將該碳簇分子奈米粉末沈積在該基板表面上,從而於該基板表面上形成自組裝且高度均勻之碳簇分子陣列。本發明亦提供一種由此製得之碳簇分子陣列嵌入式基板,其具有優異之場發射性能,可作為場發射器用於任何場發射顯示器(Field Emission Display;FED)中。最後,本發明亦提供一種由此製得之碳簇分子陣列嵌入式基板,其可替代碳化半導體材料,作為光電元件及高溫、高功率、抗高溫或高頻率電子元件之用

VLS growth of pure and Au decorated beta-Ga2O3 nanowires for room temperature CO gas sensor and resistive memory applications

High-density single crystalline β-Ga2O3 nanowires on silicon (1 0 0) substrates were grown by vapour-liquid-solid growth method. We have characterized the pure β-Ga2O3 nanowires along with the Au-decorated β-Ga2O3 nanowires. The CO gas sensors at room temperature (RT) have been studied for pure and Au decorated nanowires with multiple-networked array and single nanowire devices. The diameter of the 1D nanostructure ranged from 127 ± 5 nm. The synthesized nanowires were studied using Field Emission Scanning Electron Microscope (FESEM), Transmission Electron Microscope (TEM), Energy Dispersive X-ray Spectroscopy (EDS), Gracing Incidence X-ray Diffraction (GI-XRD), Photoluminescence (PL), Raman spectroscopy and X-ray Photoelectron Spectroscopy (XPS). Using the Focussed Ion Beam (FIB) technique, single nanowire gas sensor devices were fabricated. Single nanowire RT CO gas sensors using the proposed Au decorated β-Ga2O3 nanowire achieved remarkable sensitivity for 100 ppm CO gas at room temperature. Besides, we have compared the RT CO gas sensing properties of multiple-networked Au decorated β-Ga2O3 nanowires with single Au-decorated β-Ga2O3 nanowire and single pure β-Ga2O3 nanowire. In addition, bipolar resistive switching property is inspected for the Au/pure β-Ga2O3 nanowires/p-Si and Au/Au decorated β-Ga2O3 nanowires/p-Si structures

Ag-Decorated Vertically Aligned ZnO Nanorods for Non-Enzymatic Glucose Sensor Applications

The non-enzymatic glucose sensing response of pure and Ag-decorated vertically aligned ZnO nanorods grown on Si substrates was investigated. The simple low-temperature hydrothermal method was employed to synthesize the ZnO NRs on the Si substrates, and then Ag decoration was achieved by sputtering. The crystal structure and surface morphologies were characterized by X-ray diffraction, field-emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). The Ag incorporation on the ZnO NR surfaces was confirmed using EDS mapping and spectra. Furthermore, the chemical states, the variation in oxygen vacancies, and the surface modifications of Ag@ZnO were investigated by XPS analysis. Both the glucose/ZnO/Si and glucose/Ag@ZnO/Si device structures were investigated for their non-enzymatic glucose sensing performances with different glucose concentrations. Based on EIS measurements and amperometric analysis, the Ag@ZnO-NR-based glucose sensor device exhibited a better sensing ability with excellent stability over time than pure ZnO NRs. The Ag@ZnO NR glucose sensor device recorded 2792 µA/(mM·cm2) sensitivity with a lowest detection limit of 1.29 µM

High-Quality Single-Crystalline β-Ga2O3 Nanowires: Synthesis to Nonvolatile Memory Applications

One of the promising nonvolatile memories of the next generation is resistive random-access memory (ReRAM). It has vast benefits in comparison to other emerging nonvolatile memories. Among different materials, dielectric films have been extensively studied by the scientific research community as a nonvolatile switching material over several decades and have reported many advantages and downsides. However, less attention has been given to low-dimensional materials for resistive memory compared to dielectric films. Particularly, β-Ga2O3 is one of the promising materials for high-power electronics and exhibits the resistive switching phenomenon. However, low-dimensional β-Ga2O3 nanowires have not been explored in resistive memory applications, which hinders further developments. In this article, we studied the resistance switching phenomenon using controlled electron flow in the 1D nanowires and proposed possible resistive switching and electron conduction mechanisms. High-density β-Ga2O3 1D-nanowires on Si (100) substrates were produced via the VLS growth technique using Au nanoparticles as a catalyst. Structural characteristics were analyzed via SEM, TEM, and XRD. Besides, EDS, CL, and XPS binding feature analyses confirmed the composition of individual elements, the possible intermediate absorption sites in the bandgap, and the bonding characteristics, along with the presence of various oxygen species, which is crucial for the ReRAM performances. The forming-free bipolar resistance switching of a single β-Ga2O3 nanowire ReRAM device and performance are discussed in detail. The switching mechanism based on the formation and annihilation of conductive filaments through the oxygen vacancies is proposed, and the possible electron conduction mechanisms in HRS and LRS states are discussed

The mechanism underlying silicon oxide based resistive random-access memory (ReRAM)

In this work, we have inspected the theoretical resistive switching properties of two ReRAM models based on heterojunction structures of Cu/SiOx nanoparticles (NPs)/Si and Si/SiOx NPs/Si, in which dielectric layers of the silica nanoparticles present dislocations at bicrystal interfaces. To validate the theoretical model, a charge storage device with the structure Cu/SiOx/Si was fabricated and its ReRAM properties were studied. Our examinations on the electrical, thermal and structural aspects of resistive switching uncovered the switching behavior relies upon the material properties and electrical characteristics of the switching layers, as well as the metal electrodes and the interfacial structure of grains within the dielectric materials. We also determined that the application of an external electric field at Grain Boundaries (GB) is crucial to resistive switching behavior. Moreover, we have demonstrated that the switching behavior is influenced by variations in the atomic structure and electronic properties, at the atomic length scale and picosecond timescale. Our findings furnish a useful reference for the future development and optimization of materials used in this technology