NiW合金基带表面c(2×2)-S超结构的硫化处理

Sulfuration of c(2×2)-S Superstructure on NiW Alloy Substrates

由于硫元素与氧元素化学特性相近,利用硫在Ni基带表面形成的c(2×2)-S超结构可以有效地控制氧化物缓冲层在Ni基带表面的织构.本研究提出将单质硫在120℃下挥发,利用单质硫在基带表面的吸附与脱附形成有序c(2×2)-S超结构的新技术路线.X光电子能谱(XPS)结果显示,采用新技术处理的金属基带表面有明显的硫元素,基带表面Ni和S的原子比例符合c(2×2)结构中S的覆盖度,即0.5的要求.在经过硫化处理后的NiW基带表面制备缓冲层,结果显示,新硫化处理技术改善了NiW基带表面的物理化学特性,有利于氧化物缓冲层的外延生长.

Because of the similarity of chemical properties between sulfur and oxygen,the formation of c（2×2）-S superstructure on the surface of NiW substrates is effective to control the texture of the epitaxial oxide buffer layers on the surface of metal Ni substrates.A new technological route was put forward to form the c（2×2）-S superstructure on the surface of substrates by the sublimation（at 120 ℃）,adsorption and desorption of elementary sulfur.The X-ray photoelectron spectra（XPS） analysis indicated that notable amount of S element can be observed on the metal substrates treated by the new method.The ratio of Ni atoms to S atoms is in accord with the coverage of c（2×2） structure which is 0.5.The results of the buffer layer prepared on the surface with c（2×2）-S superstructure showed that the new sulfuration method improves the physical and chemical properties of the surface of NiW substrates and is propitious for the growth of epitaxial oxide layers.