Growth Characteristics of Calcium Silicides Films from the Deposited Ca Films at the Different Sputtering Ar Pressure
Thin Ca films were deposited directly on Si(100) substrates at the different deposition Ar pressure using Radio Frequency (R.F.) magnetron sputtering system (MS) and subsequent annealed at 800°C for 2.5h or 1.5h in a vacuum furnace, respectively. The double-structure Ca2Si films and Ca5Si3 film are grown directly and individually on Si(100) substrates by an interdiffusion process between the deposited Ca atoms and Si bulk crystals, respectively. Experimental results indicated that the selective grown of a single phase calcium silicide in multiple silicide phases in Ca-Si system depends on sputtering condition, annealing temperature and annealing time, especially sputtering condition is the principal factor for the selective grown because it is close contacted with the morphological character, the bombardment defect, the nucleation density of a calcium silicide in a calcium silicides system by bombardment intensity and so on. Besides, 800°C is the adaptive annealing temperature for a single calcium silicide film growth. Keywords-Ca2Si; Ca5Si3; Nucleation; Semiconducting silicides; MS; Annealing
Empty electronic states of calcium silicides: An inverse-photoemission investigation in the ultraviolet photon range.
Etude des etats electroniques vides dans Ca 2 Si, CaSi et CaSi 2 par photoemission inverse. En comparant la theorie et l'experience des divergences apparaissent pour les positions de l'energie des structures observees. Ceci suggere l'importance des effets de l'etat final dans la photoemission inverse
Formation and Strength of Magnesia Whiskers
The formation of single-crystal magnesia whiskers during the compressive deformation of single crystals at room temperatures is described. These whiskers can have strengths of the order of millions of pounds per square inch. They are formed during fracture as a result of the discontinuous propagation of cracks which are mechanically relieving internal stresses resulting from plastic flow