A dynamic phosphor-silicate glass (PSG) gettering method is proposed in which the processes of the gettering of Ni by PSC and the crystallizing of α-Si into poly-Si by Ni take place simultaneously. The effects of P...A dynamic phosphor-silicate glass (PSG) gettering method is proposed in which the processes of the gettering of Ni by PSC and the crystallizing of α-Si into poly-Si by Ni take place simultaneously. The effects of PSC gettering process on the performances of solution-based metal induced crystallized (S-MIC) poly-Si materials and their thin film transistors (TFTs) are discussed. The crystallization rate is much reduced due to the fact that the Ni as a medium source of crystallization is extracted by the PSC during crystallization at the same time. The boundary between two neighbouring grains in S-MIC poly-Si with PSG looks blurrier than without PSG. Compared with the TFTs made from S-MIC poly-Si without PSC gettering, the TFTs made with PSC gettering has a reduced gate induced leakage current.展开更多
In order to synthesize high-quality type-Ⅱa large diamond, the selection of catalyst is very important, in addition to the nitrogen getter. In this paper, type-IIa large diamonds are grown under high pressure and hig...In order to synthesize high-quality type-Ⅱa large diamond, the selection of catalyst is very important, in addition to the nitrogen getter. In this paper, type-IIa large diamonds are grown under high pressure and high temperature(HPHT) by using the temperature gradient method(TGM), with adopting Ti/Cu as the nitrogen getter in Ni70Mn25Co5(abbreviated as NiMnCo) or Fe(55)Ni(29)Co(16)(abbreviated FeNiCo) catalyst. The values of nitrogen concentration(Nc) in both synthesized high-quality diamonds are less than 1 ppm, when Ti/Cu(1.6 wt%) is added in the FeNiCo or Ti/Cu(1.8 wt%) is added in the NiMnCo. The difference in solubility of nitrogen between both catalysts at HPHT is the basic reason for the different effect of Ti/Cu on eliminating nitrogen. The nitrogen-removal efficiency of Ti/Cu in the NiMnCo catalyst is less than in the FeNiCo catalyst. Additionally, a high-quality type-Ⅱa large diamond size of 5.0 mm is obtained by reducing the growth rate and keeping the nitrogen concentration of the diamond to be less than 1 ppm, when Ti/Cu(1.6 wt%) is added in the FeNiCo catalyst.展开更多
Non-evaporable getter(NEG)films are an integral part of many particle accelerators.These films provide conductance-free evenly distributed pumping,a low thermal outgassing rate,and a low photon-and electron-stimulated...Non-evaporable getter(NEG)films are an integral part of many particle accelerators.These films provide conductance-free evenly distributed pumping,a low thermal outgassing rate,and a low photon-and electron-stimulated desorption.These characteristics make it an ideal solution for resolving the non-uniform pressure distribution in conductance-limited narrow vacuum tubes.In this study,ternary Ti-Zr-V films were deposited on Si substrates and Ag-Cu(Ag 0.085 wt%)tubes with an inner diameter of 22 mm.All Ti-Zr-V films were prepared from an alloy target using the same DC magnetron sputtering parameters.The compositions and corresponding chemical bonding states were analyzed by X-ray photoelectron spectroscopy after activation at different temperatures.The test particle Monte Carlo(TPMC)method was used to measure the sticking probability of the Ti-Zr-V film based on pressure readings during gas injection.The results indicate that activation commences at temperatures as low as 150℃and Ti~0,Zr~0,and V~0 exist on the surface after annealing at 180℃for 1 h.Ti-Zr-V films can be fully activated at 180℃for 24 h.The CO sticking probability reaches 0.15,with a pumping capacity of 1 monolayer.展开更多
An accelerator storage ring needs clean ultrahigh vacuum.A TiZrV non-evaporable getter(NEG) film deposited on interior walls of the chamber can realize distributed pumping,effective vacuum improvement and reduced long...An accelerator storage ring needs clean ultrahigh vacuum.A TiZrV non-evaporable getter(NEG) film deposited on interior walls of the chamber can realize distributed pumping,effective vacuum improvement and reduced longitudinal pressure gradient.But accumulation of pollutants such as N_2 and O_2 will decrease the adsorption ability of the NEG,leading to a reduction of NEG lifetime.Therefore,an NEG thin film coated with a layer of Pd,which has high diffusion rate and absorption ability for H_2,can extend the service life of NEG and improve the pumping rate of H_2 as well.In this paper,with argon as discharge gas,a magnetron sputtering method is adopted to prepare TiZrV-Pd films in a long straight pipe.By SEM measurement,deposition rates of TiZrV-Pd films are analyzed under different deposition parameters,such as magnetic field strength,gas flow rate,discharge current,discharge voltage and working pressure.By comparing the experimental results with the simulation results based on Sigmund's theory,the Pd deposition rate C can be estimated by the sputtered depth.展开更多
基金Project supported by the National High Technology Research and Developments Program of China (Grant No 004AA33570)Key Project of National Natural Science Foundation of China (NSFC) (Grant No 60437030)Tianjin Natural Science Foundation(Grant No 05YFJMJC01400)
文摘A dynamic phosphor-silicate glass (PSG) gettering method is proposed in which the processes of the gettering of Ni by PSC and the crystallizing of α-Si into poly-Si by Ni take place simultaneously. The effects of PSC gettering process on the performances of solution-based metal induced crystallized (S-MIC) poly-Si materials and their thin film transistors (TFTs) are discussed. The crystallization rate is much reduced due to the fact that the Ni as a medium source of crystallization is extracted by the PSC during crystallization at the same time. The boundary between two neighbouring grains in S-MIC poly-Si with PSG looks blurrier than without PSG. Compared with the TFTs made from S-MIC poly-Si without PSC gettering, the TFTs made with PSC gettering has a reduced gate induced leakage current.
基金supported by the National Natural Science Foundation of China(Grant No.11604246)the China Postdoctoral Science Foundation(Grant No.2016M592714)+2 种基金the Professional Practice Demonstration Base for Professional Degree Graduate in Material Engineering of Henan Polytechnic University,China(Grant No.2016YJD03)the Funds from the Education Department of Henan Province,China(Grant Nos.12A430010 and 17A430020)the Project for Key Science and Technology Research of Henan Province,China(Grant No.162102210275)
文摘In order to synthesize high-quality type-Ⅱa large diamond, the selection of catalyst is very important, in addition to the nitrogen getter. In this paper, type-IIa large diamonds are grown under high pressure and high temperature(HPHT) by using the temperature gradient method(TGM), with adopting Ti/Cu as the nitrogen getter in Ni70Mn25Co5(abbreviated as NiMnCo) or Fe(55)Ni(29)Co(16)(abbreviated FeNiCo) catalyst. The values of nitrogen concentration(Nc) in both synthesized high-quality diamonds are less than 1 ppm, when Ti/Cu(1.6 wt%) is added in the FeNiCo or Ti/Cu(1.8 wt%) is added in the NiMnCo. The difference in solubility of nitrogen between both catalysts at HPHT is the basic reason for the different effect of Ti/Cu on eliminating nitrogen. The nitrogen-removal efficiency of Ti/Cu in the NiMnCo catalyst is less than in the FeNiCo catalyst. Additionally, a high-quality type-Ⅱa large diamond size of 5.0 mm is obtained by reducing the growth rate and keeping the nitrogen concentration of the diamond to be less than 1 ppm, when Ti/Cu(1.6 wt%) is added in the FeNiCo catalyst.
基金supported by the National Natural Science Foundation of China(Nos.11975226,11905219)the Fundamental Research Funds for the Central Universities(No.WK2310000071)the National Key Research and Development Program of China(2016YFA0402004).
文摘Non-evaporable getter(NEG)films are an integral part of many particle accelerators.These films provide conductance-free evenly distributed pumping,a low thermal outgassing rate,and a low photon-and electron-stimulated desorption.These characteristics make it an ideal solution for resolving the non-uniform pressure distribution in conductance-limited narrow vacuum tubes.In this study,ternary Ti-Zr-V films were deposited on Si substrates and Ag-Cu(Ag 0.085 wt%)tubes with an inner diameter of 22 mm.All Ti-Zr-V films were prepared from an alloy target using the same DC magnetron sputtering parameters.The compositions and corresponding chemical bonding states were analyzed by X-ray photoelectron spectroscopy after activation at different temperatures.The test particle Monte Carlo(TPMC)method was used to measure the sticking probability of the Ti-Zr-V film based on pressure readings during gas injection.The results indicate that activation commences at temperatures as low as 150℃and Ti~0,Zr~0,and V~0 exist on the surface after annealing at 180℃for 1 h.Ti-Zr-V films can be fully activated at 180℃for 24 h.The CO sticking probability reaches 0.15,with a pumping capacity of 1 monolayer.
基金supported by the National Natural Science Funds of China(No.11205155)Fundamental Research Funds for the Central Universities(WK2310000041)
文摘An accelerator storage ring needs clean ultrahigh vacuum.A TiZrV non-evaporable getter(NEG) film deposited on interior walls of the chamber can realize distributed pumping,effective vacuum improvement and reduced longitudinal pressure gradient.But accumulation of pollutants such as N_2 and O_2 will decrease the adsorption ability of the NEG,leading to a reduction of NEG lifetime.Therefore,an NEG thin film coated with a layer of Pd,which has high diffusion rate and absorption ability for H_2,can extend the service life of NEG and improve the pumping rate of H_2 as well.In this paper,with argon as discharge gas,a magnetron sputtering method is adopted to prepare TiZrV-Pd films in a long straight pipe.By SEM measurement,deposition rates of TiZrV-Pd films are analyzed under different deposition parameters,such as magnetic field strength,gas flow rate,discharge current,discharge voltage and working pressure.By comparing the experimental results with the simulation results based on Sigmund's theory,the Pd deposition rate C can be estimated by the sputtered depth.