The results of observation of different structuring techniques of thin metal layers applied in micro system technologies are presented. The Ti V getter films formed by magnetron sputtering have been explored using sca...The results of observation of different structuring techniques of thin metal layers applied in micro system technologies are presented. The Ti V getter films formed by magnetron sputtering have been explored using scanning electron and atomic-force microscopy, Brunauer-Emmett-Teller method, thermogravimetric analysis and fractal geometry. The film sorption capacity for hydrogen given by thermogravimetry was of 7.7 m3·Pa·g-1. To estimate the effective surface area, the fractal geometry tools were used and the calculated value of the specific surface area was about 155 m2/m3. The second object under investigation was a structure composed of micro- and mesoporous silicon and copper layer deposited electrochemically on the pore walls. Porous silicon when coupled with a reactive metal or alloy is expected to be an effective getter for micro system techniques. The use of porous silicon and specific conditions of depositions allows to form the structure of complex fractal type with a specific surface area of 167 m2/cm3.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
Hazy backside gettering of boron-doped <111> siljcon wafer with a-Si: H film deposited by rf glow discharge technique (rf-GD) has been investigated by SEM, optical microscope and preferential etching tech- lique...Hazy backside gettering of boron-doped <111> siljcon wafer with a-Si: H film deposited by rf glow discharge technique (rf-GD) has been investigated by SEM, optical microscope and preferential etching tech- lique. lt is evident that the deposited film can effectively getter the haze after annealing at l l00℃in wet oxy- len ambient for 120 min. The pre-crystallization annealing at 650℃ in argon ambient for 10 min enhances the gettering effectiveness. The low temperature(200～300℃) process of growing extrinsic gettering film reduces the processing contamination.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
Introduction The pumping performance of getter materials has becoming one of the hotspots in accelerator field.The recovery of pumping performance after air venting,also called aging effect,is important for applicatio...Introduction The pumping performance of getter materials has becoming one of the hotspots in accelerator field.The recovery of pumping performance after air venting,also called aging effect,is important for applications in accelerators.Materials and methods In this work,we investigated the aging effect of Ti-V-Zr-Hf-and Ti-V-Zr-coated copper tubular chambers,and the effect of initial air exposure time on the aging properties.The samples presented hierarchically micro/nano-structures and showed a featured aging curve,giving about 9 effective pumping cycles.Conclusion The pumping performance is inversely correlated with air exposure time suggesting that the getter coated cham-bers should be properly preserved before applied as a"pump".展开更多
TiZrV film is mainly applied in the ultra-high vacuum pipes of storage rings. Thin fihn coatings of palladium, which are added onto the TiZrV film to increase the service life of nonevaporable getters and enhance H2 p...TiZrV film is mainly applied in the ultra-high vacuum pipes of storage rings. Thin fihn coatings of palladium, which are added onto the TiZrV film to increase the service life of nonevaporable getters and enhance H2 pumping speed, were deposited on the inner face of stainless steel pipes by dc magnetron sputtering using argon gas as the sputtering gas. The TiZrV-Pd film properties were investigated by atomic force microscope （AFM）, scanning electron microscope （SEM）, X-ray photoelectron spectroscopy （XPS） and X-Ray Diffraction （XRD）. The grain size of TiZrV and Pd films were about 0.42 1.3 nm and 8.5-18.25 nm respectively. It was found that the roughness of TiZrV films is small, about 2 4 nm, but for Pd film it is large, about 17 19 nm. The PP At. % of Pd in TiZrV/Pd films varied from 86.84 to 87.56 according to the XPS test results.展开更多
文摘The results of observation of different structuring techniques of thin metal layers applied in micro system technologies are presented. The Ti V getter films formed by magnetron sputtering have been explored using scanning electron and atomic-force microscopy, Brunauer-Emmett-Teller method, thermogravimetric analysis and fractal geometry. The film sorption capacity for hydrogen given by thermogravimetry was of 7.7 m3·Pa·g-1. To estimate the effective surface area, the fractal geometry tools were used and the calculated value of the specific surface area was about 155 m2/m3. The second object under investigation was a structure composed of micro- and mesoporous silicon and copper layer deposited electrochemically on the pore walls. Porous silicon when coupled with a reactive metal or alloy is expected to be an effective getter for micro system techniques. The use of porous silicon and specific conditions of depositions allows to form the structure of complex fractal type with a specific surface area of 167 m2/cm3.
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.
文摘Hazy backside gettering of boron-doped <111> siljcon wafer with a-Si: H film deposited by rf glow discharge technique (rf-GD) has been investigated by SEM, optical microscope and preferential etching tech- lique. lt is evident that the deposited film can effectively getter the haze after annealing at l l00℃in wet oxy- len ambient for 120 min. The pre-crystallization annealing at 650℃ in argon ambient for 10 min enhances the gettering effectiveness. The low temperature(200～300℃) process of growing extrinsic gettering film reduces the processing contamination.
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.
基金supported by High Energy Photon Source(HEPS),a major national science and technology infrastructureprovided by National Development and Reform Commission(Grant No.发改高技(2017)2173号)
文摘Introduction The pumping performance of getter materials has becoming one of the hotspots in accelerator field.The recovery of pumping performance after air venting,also called aging effect,is important for applications in accelerators.Materials and methods In this work,we investigated the aging effect of Ti-V-Zr-Hf-and Ti-V-Zr-coated copper tubular chambers,and the effect of initial air exposure time on the aging properties.The samples presented hierarchically micro/nano-structures and showed a featured aging curve,giving about 9 effective pumping cycles.Conclusion The pumping performance is inversely correlated with air exposure time suggesting that the getter coated cham-bers should be properly preserved before applied as a"pump".
基金Supported by National Natural Science Funds of China(11205155)Fundamental Research Funds for the Central Universities(WK2310000041)
文摘TiZrV film is mainly applied in the ultra-high vacuum pipes of storage rings. Thin fihn coatings of palladium, which are added onto the TiZrV film to increase the service life of nonevaporable getters and enhance H2 pumping speed, were deposited on the inner face of stainless steel pipes by dc magnetron sputtering using argon gas as the sputtering gas. The TiZrV-Pd film properties were investigated by atomic force microscope （AFM）, scanning electron microscope （SEM）, X-ray photoelectron spectroscopy （XPS） and X-Ray Diffraction （XRD）. The grain size of TiZrV and Pd films were about 0.42 1.3 nm and 8.5-18.25 nm respectively. It was found that the roughness of TiZrV films is small, about 2 4 nm, but for Pd film it is large, about 17 19 nm. The PP At. % of Pd in TiZrV/Pd films varied from 86.84 to 87.56 according to the XPS test results.
