Germanium-tin films with rather high Sn content (28.04% and 29.61%) are deposited directly on Si (100) and Si (111) substrates by magnetron sputtering. The mechanism of the effect of rapid thermal annealing on t...Germanium-tin films with rather high Sn content (28.04% and 29.61%) are deposited directly on Si (100) and Si (111) substrates by magnetron sputtering. The mechanism of the effect of rapid thermal annealing on the Sn surface segregation of Ge1-xSnx films is investigated by x-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The x-ray diffraction (XRD) is also performed to determine the crystallinities of the Ge1-xSnx films. The experimental results indicate that root mean square (RMS) values of the annealed samples are comparatively small and have no noticeable changes for the as-grown sample when annealing temperature is below 400℃. The diameter of the Sn three-dimensional (3D) island becomes larger than that of an as-grown sample when the annealing temperature is 700℃. In addition, the Sn surface composition decreases when annealing temperature ranges from 400℃ to 700℃. However, Sn bulk compositions in samples A and B are kept almost unchanged when the annealing temperature is below 600℃. The present investigation demonstrates that the crystallinity of Ge1-xSnx/Si (111) has no obvious advantage over that of Ge1-xSnx/Si (100) and the selection of Si (111) substrate is an effective method to improve the surface morphologies of Ge1-xSnx films. We also find that more severe Sn surface segregation occurs in the Ge1-xSnx/Si (111) sample during annealing than in the Ge1-xSnx/Si (100) sample.展开更多
A new pulsed chemical vapor deposition(PCVD) process has been developed to fabricate iron(Fe) and iron carbide(Fe1-xCx) thin films at low temperature range from 150 ℃ to 230 ℃.The process employs bis(1,4-di-ter...A new pulsed chemical vapor deposition(PCVD) process has been developed to fabricate iron(Fe) and iron carbide(Fe1-xCx) thin films at low temperature range from 150 ℃ to 230 ℃.The process employs bis(1,4-di-tert-butyl-1,3-diazabutadienyl)iron(Ⅱ) as iron source and hydrogen gas or hydrogen plasma as the coreactant.The films deposited with hydrogen gas are demonstrated polycrystalline with body-centered cubic Fe.However,for the films deposited with hydrogen plasma,the amorphous phase of iron carbide is obtained.The influence of the deposition temperature on iron and iron carbide characteristics have been investigated.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61474085 and 61704130)the Science Research Plan in Shaanxi Province,China(Grant No.2016GY-085)+1 种基金the Opening Project of Key Laboratory of Microelectronic Devices&Integrated Technology,Institute of Microelectronics,Chinese Academy of Sciences(Grant No.90109162905)the Fundamental Research Funds for the Central Universities,China(Grant No.61704130)
文摘Germanium-tin films with rather high Sn content (28.04% and 29.61%) are deposited directly on Si (100) and Si (111) substrates by magnetron sputtering. The mechanism of the effect of rapid thermal annealing on the Sn surface segregation of Ge1-xSnx films is investigated by x-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The x-ray diffraction (XRD) is also performed to determine the crystallinities of the Ge1-xSnx films. The experimental results indicate that root mean square (RMS) values of the annealed samples are comparatively small and have no noticeable changes for the as-grown sample when annealing temperature is below 400℃. The diameter of the Sn three-dimensional (3D) island becomes larger than that of an as-grown sample when the annealing temperature is 700℃. In addition, the Sn surface composition decreases when annealing temperature ranges from 400℃ to 700℃. However, Sn bulk compositions in samples A and B are kept almost unchanged when the annealing temperature is below 600℃. The present investigation demonstrates that the crystallinity of Ge1-xSnx/Si (111) has no obvious advantage over that of Ge1-xSnx/Si (100) and the selection of Si (111) substrate is an effective method to improve the surface morphologies of Ge1-xSnx films. We also find that more severe Sn surface segregation occurs in the Ge1-xSnx/Si (111) sample during annealing than in the Ge1-xSnx/Si (100) sample.
基金financially supported by National Natural Science Foundation of China(No.11775028)Collaborative Innovation Center of Green Printing&Publishing Technology(No.15208)Beijing Institute of Graphic Communication Project(Nos.Ea201801 04190119001-020 and 12000400001)
文摘A new pulsed chemical vapor deposition(PCVD) process has been developed to fabricate iron(Fe) and iron carbide(Fe1-xCx) thin films at low temperature range from 150 ℃ to 230 ℃.The process employs bis(1,4-di-tert-butyl-1,3-diazabutadienyl)iron(Ⅱ) as iron source and hydrogen gas or hydrogen plasma as the coreactant.The films deposited with hydrogen gas are demonstrated polycrystalline with body-centered cubic Fe.However,for the films deposited with hydrogen plasma,the amorphous phase of iron carbide is obtained.The influence of the deposition temperature on iron and iron carbide characteristics have been investigated.