采用电子束沉积的方法在底衬Mo(R4≈5-8.63nm)上制备了厚度为2~3gm的Sc膜,再将Sc膜在Sievert真空系统中进行吸氘。结果表明:在底衬温度为623,823,1023K时,Sc膜呈现出柱状结构,且具有(002)的择优生长;随着沉积温度从623K增大到1023K,Sc膜的(002)择优生长变强,晶粒尺寸也随之增大,这与前人报道的结构区域模型(SZMs)是一致的。Sc膜经吸氘变为了ScD2膜,ScD2膜为(111)择优生长,而且随着衬底温度的升高,择优生长也随着增强,这说明了(111)晶面的ScD2晶核是由吸氘前(002)晶面的钪晶核生长而来的;高底衬温度下制备的sc膜经吸氘后所获的ScD2膜的晶粒尺寸反而更小,这可能是由D原子在低衬底温度制备的Sc膜中较强的扩散动力学造成的。另外,提出了一种新的制备底衬材料的方法,该方法能够简单、快速的获得Sc膜的断面形貌,而且对Sc膜不会造成任何污染,且经济便宜。
Scandium films with thickness of- 2-3 ktm were deposited on Mo substrates with a surface roughness Rq≈5-8.63 nm. Subsequently, the films were converted to scandium dideuteride (SeD2) in the Sievert's apparatus. A novel substrate preparation process has been developed for a simple observation of the cross-sectional images. The effects of substrate temperatures (623, 823, 1023 K) on the initial Sc-metal film microstructure and the following ScD2 microstructure were investigated. Results indicate that Sc films show a columnar microstructure with a preferred orientation of the crystallites along the [002] direction at all the three tempertures and the (002) texture increases with increasing of the temperature. The grain sizes of Sc films deposited at higher temperature are larger than those deposited at lower temperature, consistent with the published structure zone models (SZMs). As expected, the stronger (002) texture of Sc-metal film deposited at higher temperature results in the stronger (111) texture of deuteride film, indicating that the deuteride nuclei might inherit their texture from the initial metal grains' structure. Unexpectedly, an inverse correlation appears that larger Sc-metal grains lead to smaller deuteride grains due to the improved deuterium diffusion kinetics in the more defective and fine-grained metal structure