Preparation and electrical properties of Ca5Si3 and Sr5Si3 powders

Phase selection during calcium silicide formation for layered and powder growth

“…The Ca source and Si powder were first placed in a loosely sealed glass container, and then the container was loaded into a vacuum chamber. The container was then heated and the temperature was maintained at 750 • C for 12 h [19].…”

“…[16,19], which reported for the layered growth, the Ca 2 Si and CaSi interface was formed while the Ca 5 Si 3 phase was not significantly formed. On the other hand, for powder growth, the Ca 5 Si 3 single phase powders were grown.…”

“…There are multiple silicide phases, such as CaSi 2 , CaSi, Ca 5 Si 3 and Ca 2 Si that exist in the Ca-Si system, which could lead to the simultaneous formation during its growth [14][15][16][17]. Among them, Ca 2 Si and Ca 5 Si 3 have been reported to have a semiconducting behavior [14,15,19]. It is important to understand the elemental chemical potential gradients and effective heat of formation (EHF) as certain driving forces for diffusion in the Ca-Si system, in addition to the concentration controlled phase selection.…”

Growth of Ca-Germanide and Ca-Silicide Crystals by Mechanical Alloying

“…The development of reactive deposition techniques has allowed us to grow new novel silicides, such as Ca 2 Si and Sr 2 Si [5][6][7][8]12]. In addition, a vacuum-free growth technique for the β-FeSi 2 layers or bulk preparations has been developed on the basis of the reactive deposition techniques [13].…”

“…Concerning the Ca-based silicides, the Ca 2 Si layers and bulk crystals were successfully grown using Mg 2 Si/Si and Mg 2 Si substrates, respectively [5][6][7]. Moreover, the Ca 5 Si 3 powders were obtained by the heat treatment of Si powders under Ca vapor [8]. It is important to systemically understand the science and technology of this new silicide family for further developing the sustainable optoelectronic technology using silicides and related materials.…”