A ZnO nanowire vacuum pressure sensor

Abstract

In this study, we report the growth and characterization of lateral ZnO nanowires (NWs) on ZnO:Ga/glass templates. Using x-ray diffraction and micro-Raman spectroscopy, it was found that crystal quality of the as-grown ZnO NWs is good. It was also found that the average length and average diameter of the laterally grown ZnO NWs were 5 µm and 30 nm, respectively. A vacuum pressure sensor was then fabricated using a single NW bridging across two electrodes. By measuring the current-voltage characteristics of the samples at low pressure, we found that the currents were of 17, 34.28, 57.37 and 96.06 nA for the ZnO NW measured at 1 × 10(-3) Torr, 1 × 10(-4) Torr, 3 × 10(-5) Torr and 5 × 10(-6) Torr, respectively. These values suggest that the laterally grown ZnO NWs prepared in this study are potentially useful for vacuum pressure sensing.

Probing the excitonic emission of ZnO nanoparticles using UV–VUV excitations

“…However, we can envisage another mechanism involving the surface and influencing the A band. Indeed, it is well known that the ZnO compounds are very sensitive to air and water [13,14]. This sensitivity would be increased in the case of NP due to there large surface volume ratio and could have an important influence on the emission spectra.…”

Room-temperature H2S Gas Sensor Based on Au-doped ZnFe2O4 Yolk-shell Microspheres

“…40,41 When ZnFe2O4-based sensors are exposed to air, the oxygen molecules are absorbed on the surface, and chemisorbed species are formed through obtaining electrons from the conduction band of ZnFe2O4, providing an electron-depletion layer along with the decreasing conductivity of the sensor. 42,43 Temperature determines the species observed on the surface of ZnFe2O4; for instance, at room temperature O2 -is chemisorbed. 44 While it exposed to H2S gas, the H2S molecules react with the previously absorbed oxygen species.…”

Formaldehyde sensing mechanism of SnO2 nanowires grown on-chip by sputtering techniques

“…In order to have the advantages of nanomaterials but applicable at commercial level, some works have been focused on developing on-chip nanowire growing procedures. 6,7 The methods reported in literature are usually based on thermal evaporation and chemical vapour deposition techniques. [8][9][10] The source material is a metallic powder placed in an alumina crucible inside a horizontal quartz tube furnace.…”