电泳法制备的石墨烯阴极由于其独特的优势,目前已经成为石墨烯阴极的主要制备方法。因此,研究电泳电流以及电泳浓度对石墨烯阴极表面形貌和发射性能的影响具有十分重大的意义。通过扫描电镜、拉曼光谱和超高真空测试平台对其进行形貌和...电泳法制备的石墨烯阴极由于其独特的优势,目前已经成为石墨烯阴极的主要制备方法。因此,研究电泳电流以及电泳浓度对石墨烯阴极表面形貌和发射性能的影响具有十分重大的意义。通过扫描电镜、拉曼光谱和超高真空测试平台对其进行形貌和性能表征。结果表明,电泳浓度和电泳电流均对石墨烯阴极的表面形貌和发射性能有较大影响。在电泳电流为4 m A,电泳液中石墨烯的浓度为0.55 g/L时,其发射性能最佳,开启场强约为4.7 V/μm。展开更多
Hydrogenated amorphous silicon (a-Si:H) thin films were deposited by plasma-enhanced vapor deposition (PECVD) at different silane temperatures (Tg) before glow-discharge. The effect of Tg on the amorphous network and ...Hydrogenated amorphous silicon (a-Si:H) thin films were deposited by plasma-enhanced vapor deposition (PECVD) at different silane temperatures (Tg) before glow-discharge. The effect of Tg on the amorphous network and optoelectronic properties of the films has been investigated by Raman scattering spectra, ellipsometric transmittance spectra, and dark conductivity measurement, respectively. The results show that the increase in Tg leads to an improved ordering of amorphous network on the short and intermediate scales and an increase of both refractive index and absorption coefficient in a-Si:H thin films. It is indicated that the dark conductivity increases by two orders of magnitude when Tg is raised from room temperature (RT) to 433 K. The continuous ordering of amorphous network of a-Si:H thin films deposited at a higher Tg is the main cause for the increase of dark conductivity.展开更多
According to the different penetration depths for the incident lights of 472 nm and 532 nm in hydrogenated amorphous silicon (a-Si:H) thin films, the depth profile study on Raman spectra of a-Si:H films was carried ou...According to the different penetration depths for the incident lights of 472 nm and 532 nm in hydrogenated amorphous silicon (a-Si:H) thin films, the depth profile study on Raman spectra of a-Si:H films was carried out. The network ordering evolution in the near surface and interior region of the unirradiated and irradiated a-Si:H films was investigated. The results show that there is a structural improvement in the shortand intermediate-range order towards the surface of the unirradiated a-Si:H films. The amorphous silicon network in the near and interior region becomes more disordered on the shortand intermediate-range scales after being irradiated with high energy electrons. However, the surface of the irradiated films becomes more disordered in comparison with their interior region, indicating that the created defects caused by electron irradiation are concentrated in the near surface of the irradiated films. Annealing eliminates the irradiation effects on a-Si:H thin films and the structural order of the irradiated films is similar to that of the unirradiated ones after being annealed. There exists a structural improvement in the shortand intermediate-range order towards the surface of the irradiated a-Si:H films after being annealed.展开更多
Lanthanum hexaboride (LaB 6) thin films were used as protective layers in alternating current plasma display panels (AC-PDPs).The firing voltages and discharge delay time of protective LaB 6 thin films were evaluated ...Lanthanum hexaboride (LaB 6) thin films were used as protective layers in alternating current plasma display panels (AC-PDPs).The firing voltages and discharge delay time of protective LaB 6 thin films were evaluated and compared with the conventional protective MgO layers in planar-type test panels filled with 5%-15% Ne-Xe.By employing LaB 6 thin films as protective layers,both the firing voltages and discharge delay time decreased drastically.Improvements in the discharge properties of the LaB 6 thin film could be attributed to the lower work function,offering more priming electrons during the discharge process.展开更多
The relationship between structure and electronic properties of phosphorus-doped hydrogenated amorphous silicon(a-Si:H) thin films was investigated.Samples with different features were prepared by plasma enhanced chem...The relationship between structure and electronic properties of phosphorus-doped hydrogenated amorphous silicon(a-Si:H) thin films was investigated.Samples with different features were prepared by plasma enhanced chemical vapor deposition(PECVD) at various substrate temperatures.Raman spectroscopy and Fourier transform infrared(FTIR) spectroscopy were used to evaluate the structural evolution,meanwhile,electronic-spin resonance(ESR) and optical measurement were applied to explore the electronic properties of P-doped a-Si:H thin films.The results revealed that the changes in materials structure affect directly the electronic properties and the doping efficiency of dopant.展开更多
文摘电泳法制备的石墨烯阴极由于其独特的优势,目前已经成为石墨烯阴极的主要制备方法。因此,研究电泳电流以及电泳浓度对石墨烯阴极表面形貌和发射性能的影响具有十分重大的意义。通过扫描电镜、拉曼光谱和超高真空测试平台对其进行形貌和性能表征。结果表明,电泳浓度和电泳电流均对石墨烯阴极的表面形貌和发射性能有较大影响。在电泳电流为4 m A,电泳液中石墨烯的浓度为0.55 g/L时,其发射性能最佳,开启场强约为4.7 V/μm。
基金Supported by the National Outstanding Young Scientists Foundation of China (Grant No.60425101)the Science Foundation of General Armament Department of China (Grant No.06DZ02)
文摘Hydrogenated amorphous silicon (a-Si:H) thin films were deposited by plasma-enhanced vapor deposition (PECVD) at different silane temperatures (Tg) before glow-discharge. The effect of Tg on the amorphous network and optoelectronic properties of the films has been investigated by Raman scattering spectra, ellipsometric transmittance spectra, and dark conductivity measurement, respectively. The results show that the increase in Tg leads to an improved ordering of amorphous network on the short and intermediate scales and an increase of both refractive index and absorption coefficient in a-Si:H thin films. It is indicated that the dark conductivity increases by two orders of magnitude when Tg is raised from room temperature (RT) to 433 K. The continuous ordering of amorphous network of a-Si:H thin films deposited at a higher Tg is the main cause for the increase of dark conductivity.
基金Supported by the National Outstanding Young Scientists Foundation of China (Grant No. 60425101)the Science Foundation of General Armament Department of China (Grant No. 06DZ02)
文摘According to the different penetration depths for the incident lights of 472 nm and 532 nm in hydrogenated amorphous silicon (a-Si:H) thin films, the depth profile study on Raman spectra of a-Si:H films was carried out. The network ordering evolution in the near surface and interior region of the unirradiated and irradiated a-Si:H films was investigated. The results show that there is a structural improvement in the shortand intermediate-range order towards the surface of the unirradiated a-Si:H films. The amorphous silicon network in the near and interior region becomes more disordered on the shortand intermediate-range scales after being irradiated with high energy electrons. However, the surface of the irradiated films becomes more disordered in comparison with their interior region, indicating that the created defects caused by electron irradiation are concentrated in the near surface of the irradiated films. Annealing eliminates the irradiation effects on a-Si:H thin films and the structural order of the irradiated films is similar to that of the unirradiated ones after being annealed. There exists a structural improvement in the shortand intermediate-range order towards the surface of the irradiated a-Si:H films after being annealed.
基金supported by the Fundamental Research Funds for the Central Universities(ZYGX2010J062)
文摘Lanthanum hexaboride (LaB 6) thin films were used as protective layers in alternating current plasma display panels (AC-PDPs).The firing voltages and discharge delay time of protective LaB 6 thin films were evaluated and compared with the conventional protective MgO layers in planar-type test panels filled with 5%-15% Ne-Xe.By employing LaB 6 thin films as protective layers,both the firing voltages and discharge delay time decreased drastically.Improvements in the discharge properties of the LaB 6 thin film could be attributed to the lower work function,offering more priming electrons during the discharge process.
基金supported by the Fundamental Research Funds for the Central Universities
文摘The relationship between structure and electronic properties of phosphorus-doped hydrogenated amorphous silicon(a-Si:H) thin films was investigated.Samples with different features were prepared by plasma enhanced chemical vapor deposition(PECVD) at various substrate temperatures.Raman spectroscopy and Fourier transform infrared(FTIR) spectroscopy were used to evaluate the structural evolution,meanwhile,electronic-spin resonance(ESR) and optical measurement were applied to explore the electronic properties of P-doped a-Si:H thin films.The results revealed that the changes in materials structure affect directly the electronic properties and the doping efficiency of dopant.
