Novel models （2× 1） of Si（001）-SiO2 interface structure have been established. The method of the first-principle General Gradient Approximation （GGA） is employed to structurally optimize the established the...Novel models （2× 1） of Si（001）-SiO2 interface structure have been established. The method of the first-principle General Gradient Approximation （GGA） is employed to structurally optimize the established theoretical models under the K-point space of periodic boundary condition. The structures after optimization have been analyzed, and the results show that the interfaces present in disordered state and both Si-O-Si and Si=O structures exist. Meanwhile, the bonding of surface structure is analyzed via the graphics of electron localization function（ELF）.展开更多
A CuPc/SiO2 sample is fabricated. Its morphology is characterized by atomic force microscopy, and the electron states are investigated by X-ray photoelectron spectroscopy. In order to investigate these spectra in deta...A CuPc/SiO2 sample is fabricated. Its morphology is characterized by atomic force microscopy, and the electron states are investigated by X-ray photoelectron spectroscopy. In order to investigate these spectra in detail, all of these spectra are normalized to the height of the most intense peak,and each component is fitted with a single Gaussian function. Analysis shows that the O element has great bearing on the electron states and that SiO2 layers produced by spurting technology are better than those produced by oxidation technology.展开更多
Slag movement on SiO2-based prism refractories in different slag systems was observed. The cross section shape evolution mechanism was discussed. Two types of shape evolution appear. For PbO-SiO2 slag whose surface te...Slag movement on SiO2-based prism refractories in different slag systems was observed. The cross section shape evolution mechanism was discussed. Two types of shape evolution appear. For PbO-SiO2 slag whose surface tension improves with SiO2 concentration, slag film flows up along four edges under axial Marangoni shear force and wettability. Then, it flows down along four lateral faces under gravity. Corrosion rate at edges is larger than that on lateral faces due to different SiO2 solubilities of ascending and descending flow. Prism cross section shape changes from square to round. For FetO-SiO2 slag whose surface tension reduces with the increase of SiO2 concentration, slag film flows up under the inflence of wettability. Then, it flows down under Marangoni shear force and gravity. Compared to four edges, slag is mainly up and down on four lateral faces due to larger surface tension and size. So, prism cross section shape keeps square.展开更多
用 H2 和 Ga_2O_3的高温反应形成元素 Ga 的恒定表面源,通过 SiO_2-Si 复合结构实现了 Ga 在 Si 中的高均匀性掺杂;利用二次离子质谱分析(SIMS)、扩展电阻(SRP)、四探针测试等方法,对 P 型杂质 Ga 在 SiO_2薄膜、SiO_2-Si 两固相接触的...用 H2 和 Ga_2O_3的高温反应形成元素 Ga 的恒定表面源,通过 SiO_2-Si 复合结构实现了 Ga 在 Si 中的高均匀性掺杂;利用二次离子质谱分析(SIMS)、扩展电阻(SRP)、四探针测试等方法,对 P 型杂质 Ga 在 SiO_2薄膜、SiO_2-Si 两固相接触的内界面、近 Si 表面的热分布进行分析;揭示出开管方式扩散 Ga 的实质是由 SiO_2薄膜对 Ga 原子的快速输运及其在 SiO_2-Si 内界面分凝效应两者统一的必然结果;并对该过程 Ga 杂质浓度分布机理进行了分析和讨论。展开更多
Total dose effects and single event effects on radiation-hardened power vertical double-diffusion metal oxide semiconductor（VDMOS） devices with composite SiO2-Si3N4 film gates are investigated.The relationships amon...Total dose effects and single event effects on radiation-hardened power vertical double-diffusion metal oxide semiconductor（VDMOS） devices with composite SiO2-Si3N4 film gates are investigated.The relationships among the important electrical parameters of the samples with different thickness SiO2-Si3N4 films,such as threshold voltage,breakdown voltage,and on-state resistance in accumulated dose,are discussed.The total dose experiment results show that the breakdown voltage and the on-state resistance barely change with the accumulated dose.However,the relationships between the threshold voltages of the samples and the accumulated dose are more complex,and not only positively drift,but also negatively drift.At the end of the total dose experiment,we select the group of samples which have the smaller threshold voltage shift to carry out the single event effect studies.We find that the samples with appropriate thickness ratio SiO2-Si3N4 films have a good radiation-hardening ability.This method may be useful in solving both the SEGR and the total dose problems with the composite SiO2-Si3N4 films.展开更多
Novel SiO2/BiOCl composites were fabricated by decorating BiOCl nanosheets with SiO2 nanoparticles via a simple hydrothermal process. The as-prepared pure BiOCl and SiO2/BiOCl composites were intensively characterized...Novel SiO2/BiOCl composites were fabricated by decorating BiOCl nanosheets with SiO2 nanoparticles via a simple hydrothermal process. The as-prepared pure BiOCl and SiO2/BiOCl composites were intensively characterized by various techniques such as XRD, FT-IR, SEM/TEM, BET, UV-vis, DRS, XPS, and photocurrent measurements. The SiO2/BiOCl composite nanosheets displayed high photocatalytic activity and excellent stability in the degradation of organic pollutants such as phenol, bisphenol A (BPA), and rhodamine B (RhB). With respect to those over bare BiOCl, the degradation rates of RhB, BPA, and phenol over 1.88% SiO2/BiOCl increased 16.5%, 29.0%, and 38.7%, respectively. Radical capturing results suggested that h^+ is the major reactive species and that hydroxyl (·OH) and superoxide (·O2^-) radicals could also be involved in the degradation of organic pollutants. The enhanced photocatalytic performances of SiO2/BiOCl composites can be mainly attributed to the improved texture and the formation of intimate SiO2/BiOCl interfaces, which largely promoted the adsorption of organic pollutants, enhanced the light harvesting, and accelerated the separation of e^– and h^+.展开更多
基金Supported by the National Grand Fundamental Research 973 Program of China (No. 51310Z07-3) and the Research Program of Application of Sichuan Department of Science and Technology (No. 02GY029-006)
文摘Novel models （2× 1） of Si（001）-SiO2 interface structure have been established. The method of the first-principle General Gradient Approximation （GGA） is employed to structurally optimize the established theoretical models under the K-point space of periodic boundary condition. The structures after optimization have been analyzed, and the results show that the interfaces present in disordered state and both Si-O-Si and Si=O structures exist. Meanwhile, the bonding of surface structure is analyzed via the graphics of electron localization function（ELF）.
文摘A CuPc/SiO2 sample is fabricated. Its morphology is characterized by atomic force microscopy, and the electron states are investigated by X-ray photoelectron spectroscopy. In order to investigate these spectra in detail, all of these spectra are normalized to the height of the most intense peak,and each component is fitted with a single Gaussian function. Analysis shows that the O element has great bearing on the electron states and that SiO2 layers produced by spurting technology are better than those produced by oxidation technology.
基金Projects(U1738101,51804023)supported by the National Natural Science Foundation of ChinaProjects(FRF-TP-18-007A1,FRF-MP-18-007)supported by Fundamental Research Funds for the Central Universities,ChinaProject(2019M650489)supported by China Postdoctoral Science Foundation
文摘Slag movement on SiO2-based prism refractories in different slag systems was observed. The cross section shape evolution mechanism was discussed. Two types of shape evolution appear. For PbO-SiO2 slag whose surface tension improves with SiO2 concentration, slag film flows up along four edges under axial Marangoni shear force and wettability. Then, it flows down along four lateral faces under gravity. Corrosion rate at edges is larger than that on lateral faces due to different SiO2 solubilities of ascending and descending flow. Prism cross section shape changes from square to round. For FetO-SiO2 slag whose surface tension reduces with the increase of SiO2 concentration, slag film flows up under the inflence of wettability. Then, it flows down under Marangoni shear force and gravity. Compared to four edges, slag is mainly up and down on four lateral faces due to larger surface tension and size. So, prism cross section shape keeps square.
文摘用 H2 和 Ga_2O_3的高温反应形成元素 Ga 的恒定表面源,通过 SiO_2-Si 复合结构实现了 Ga 在 Si 中的高均匀性掺杂;利用二次离子质谱分析(SIMS)、扩展电阻(SRP)、四探针测试等方法,对 P 型杂质 Ga 在 SiO_2薄膜、SiO_2-Si 两固相接触的内界面、近 Si 表面的热分布进行分析;揭示出开管方式扩散 Ga 的实质是由 SiO_2薄膜对 Ga 原子的快速输运及其在 SiO_2-Si 内界面分凝效应两者统一的必然结果;并对该过程 Ga 杂质浓度分布机理进行了分析和讨论。
文摘Total dose effects and single event effects on radiation-hardened power vertical double-diffusion metal oxide semiconductor（VDMOS） devices with composite SiO2-Si3N4 film gates are investigated.The relationships among the important electrical parameters of the samples with different thickness SiO2-Si3N4 films,such as threshold voltage,breakdown voltage,and on-state resistance in accumulated dose,are discussed.The total dose experiment results show that the breakdown voltage and the on-state resistance barely change with the accumulated dose.However,the relationships between the threshold voltages of the samples and the accumulated dose are more complex,and not only positively drift,but also negatively drift.At the end of the total dose experiment,we select the group of samples which have the smaller threshold voltage shift to carry out the single event effect studies.We find that the samples with appropriate thickness ratio SiO2-Si3N4 films have a good radiation-hardening ability.This method may be useful in solving both the SEGR and the total dose problems with the composite SiO2-Si3N4 films.
基金funding from the National Natural Science Foundation of China (21567008, 21707055)the Program for Innovative Research Team of Guangdong University of Petrochemical Technology+4 种基金the Yangfan talents Project of Guangdong Provincethe Innovation-driven “5511” Program in Jiangxi Province (20165BCB18014)the Funding Program for Academic and Technological Leaders of Major Disciplines in Jiangxi Province (20172BCB22018)the Program for New Century Excellent Talents in Fujian Province Universitythe Natural Science Foundation for Distinguished Young Scholars of Hunan Province, China (2017JJ1026)~~
文摘Novel SiO2/BiOCl composites were fabricated by decorating BiOCl nanosheets with SiO2 nanoparticles via a simple hydrothermal process. The as-prepared pure BiOCl and SiO2/BiOCl composites were intensively characterized by various techniques such as XRD, FT-IR, SEM/TEM, BET, UV-vis, DRS, XPS, and photocurrent measurements. The SiO2/BiOCl composite nanosheets displayed high photocatalytic activity and excellent stability in the degradation of organic pollutants such as phenol, bisphenol A (BPA), and rhodamine B (RhB). With respect to those over bare BiOCl, the degradation rates of RhB, BPA, and phenol over 1.88% SiO2/BiOCl increased 16.5%, 29.0%, and 38.7%, respectively. Radical capturing results suggested that h^+ is the major reactive species and that hydroxyl (·OH) and superoxide (·O2^-) radicals could also be involved in the degradation of organic pollutants. The enhanced photocatalytic performances of SiO2/BiOCl composites can be mainly attributed to the improved texture and the formation of intimate SiO2/BiOCl interfaces, which largely promoted the adsorption of organic pollutants, enhanced the light harvesting, and accelerated the separation of e^– and h^+.
