Surfactant-assisted Co film epitaxy growth on Cu(111)using Pb as a surfactant was studied by means of Auger electron spectra and synchrotron radiation photoemission spectra.The results reveal that with increasing the ...Surfactant-assisted Co film epitaxy growth on Cu(111)using Pb as a surfactant was studied by means of Auger electron spectra and synchrotron radiation photoemission spectra.The results reveal that with increasing the Co thickness most of the Pb atoms always float on the surface.Compared with 0.7ML(monolayer)Pb,the Co film with 1.5 ML Pb surfactant has more layer-by-layer growth on Cu(111).The predeposited Pb layer can suppress the intralayer diffusion on the Cu(111)surface and effectively increase the Co island density at the initial stage of Co growth.On the contrary,a Pb-Co surface alloy was found during the Co film growth;this may hinder the interlayer diffusion of the deposited Co atoms,which is unfavorable to the layer-by-layer growth.The Pb-Co is also considered to be the main reason why some Pb atoms have been buried in the Co films.展开更多
The reactions of superthin Pb Hlms on a Cu(111)surface with respect to the coverage of Pb and annealing have been studied by synchrotron radiation photoemission.The submonolayer Pb atoms deposited at room temperature ...The reactions of superthin Pb Hlms on a Cu(111)surface with respect to the coverage of Pb and annealing have been studied by synchrotron radiation photoemission.The submonolayer Pb atoms deposited at room temperature are distributed on the Cu(111)surface as two-dimensional(2D)islands.Annealing to 200℃ gives rise to Pb-Cu surface alloy formation.Analyses show that the surface alloy occurs only in the first layer of the Cu(111)surface.As a surfactant,Pb can promote 2D layer-by-layer growth of thin Hlms on Cu(111),but the Pb~Cu surface alloying may have an unfavorable effect on the activation process.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos.19890310 and 19874003.
文摘Surfactant-assisted Co film epitaxy growth on Cu(111)using Pb as a surfactant was studied by means of Auger electron spectra and synchrotron radiation photoemission spectra.The results reveal that with increasing the Co thickness most of the Pb atoms always float on the surface.Compared with 0.7ML(monolayer)Pb,the Co film with 1.5 ML Pb surfactant has more layer-by-layer growth on Cu(111).The predeposited Pb layer can suppress the intralayer diffusion on the Cu(111)surface and effectively increase the Co island density at the initial stage of Co growth.On the contrary,a Pb-Co surface alloy was found during the Co film growth;this may hinder the interlayer diffusion of the deposited Co atoms,which is unfavorable to the layer-by-layer growth.The Pb-Co is also considered to be the main reason why some Pb atoms have been buried in the Co films.
基金Supported by the National Natural Sciences Foundation of China under Grant Nos.19890310 and 19874003.
文摘The reactions of superthin Pb Hlms on a Cu(111)surface with respect to the coverage of Pb and annealing have been studied by synchrotron radiation photoemission.The submonolayer Pb atoms deposited at room temperature are distributed on the Cu(111)surface as two-dimensional(2D)islands.Annealing to 200℃ gives rise to Pb-Cu surface alloy formation.Analyses show that the surface alloy occurs only in the first layer of the Cu(111)surface.As a surfactant,Pb can promote 2D layer-by-layer growth of thin Hlms on Cu(111),but the Pb~Cu surface alloying may have an unfavorable effect on the activation process.