Processing effects on microstructure in Er and ErD2 thin-films

Abstract

a b s t r a c tErbium metal thin-films have been deposited on molybdenum-on-silicon substrates and then converted to erbium dideuteride (ErD 2 ). Here, we study the effects of deposition temperature (%300 or 723 K) and deposition rate (1 or 20 nm/s) upon the initial Er metal microstructure and subsequent ErD 2 microstructure. We find that low deposition temperature and low deposition rate lead to small Er metal grain sizes, and high deposition temperature and deposition rate led to larger Er metal grain sizes, consistent with published models of metal thin-film growth. ErD 2 grain sizes are strongly influenced by the prior-metal grain size, with small metal grains leading to large ErD 2 grains. A novel sample preparation technique for electron backscatter diffraction of air-sensitive ErD 2 was developed, and allowed the quantitative measurement of ErD 2 grain size and crystallographic texture. Finer-grained ErD 2 showed a strong (1 1 1) fiber texture, whereas larger grained ErD 2 had only weak texture. We hypothesize that this inverse correlation may arise from improved hydrogen diffusion kinetics in the more defective fine-grained metal structure or due to improved nucleation in the textured large-grain Er.

In Situ Electron Microscopy of Helium Bubble Implantation in Metal Hydrides

“…In the DF-STEM images the cavities appear particularly well defined, and can be better analyzed. Er samples prepared by the FIB lift-out technique have previously been found to be similar to those prepared by grinding/polishing/ion million methods [2,6]. For the purposes of cavity formation, He and D are acceptable surrogates for 3 He and T. TRIM simulations [8] were performed to estimate the ranges and scattering of He ions during implantation into Er.…”

“…Er and ErD 2 samples were prepared from neutron tube by a FIB lift out technique using an FEI DB-235 dual beam focused ion beam/scanning electron microscope (FIB/SEM). The samples were finished with a low-kV polish [6], and placed on the same carbon coated Cu TEM grid. The Pd films investigated were either PLD or sputter deposited to a thickness ranging from nominally 25 nm to 100 nm onto a NaCl substrate.…”

Effect of Thickness of Molybdenum Nano-Interlayer on Cohesion between Molybdenum/Titanium Multilayer Film and Silicon Substrate

“…Thin film materials maintain the fantastic properties of bulk materials [1,2,3,4,5,6] and have the significant advantages of being more economic [7], having small device size [4,5] and having the new physical performance of two-dimensional material [8,9,10]. Thin film materials have been used as functional devices in the applications of semi-conductors [2,8,9,10], metal hydrides [1,4,5,11,12,13], and solar cells [14,15], etc.…”

“…Thin film materials maintain the fantastic properties of bulk materials [1,2,3,4,5,6] and have the significant advantages of being more economic [7], having small device size [4,5] and having the new physical performance of two-dimensional material [8,9,10]. Thin film materials have been used as functional devices in the applications of semi-conductors [2,8,9,10], metal hydrides [1,4,5,11,12,13], and solar cells [14,15], etc. It is more conducive to the combination of multiple functional materials to form multilayer film materials [16,17], which can not only realize the unique characteristics of each material, but also give play to the characteristics of new interface materials [18,19,20] and improve their comprehensive performance [19,20,21,22,23].…”

“…Thus, the design of new substrates for high quality Ti film growth is in demand. Single crystal Si is a candidate substrate material due to its properties of high thermal and electrical conductivity [5,11,41]. However, the chemical reaction between Ti and Si to form a Ti-Si complex at high substrate temperature restricts its application [42,43].…”