Phase equilibria in the {Sm,Tb,Tm}–Mn–Si systems at 870/1070 K

Epitaxial samarium disilicide films on silicon (0 0 1) substrates: growth, structural and electrical properties

“…An increase in the growth temperature is clearly helpful for achieving a higher crystal quality of the SmSi 2 layer. The implied lattice constant along the growth axis is found to be 13.32 Å, in agreement with the expected bulk value of 13.3 Å [25]. It has been reported in the literature that a phase transition from orthorhombic to tetragonal occurs for SmSi 2 as the temperature is raised past 380 • C [26,27].…”

“…Upon further growth at 600-650 • C to increase the thickness, the RHEED pattern results in sharper and more intense diffraction streaks [23]. This phenomenon is not observed for layers [25]. We also observe a (2 × 2) surface reconstruction on the RHEED patterns, whose intensity progressively vanishes when the SmSi 2 surface becomes more and more rough, from the 2D to 3D character of the surface.…”

“…In our films we see no evidence for such a phase transition. The difference between the in-plane lattice constants in the two phases is slight, and the contrast between the a-and b-axis of the orthorhombic phase is very small, approximately 1% [25]. In particular, an XRD -scan of the (0 0 1) SmSi 2 plane (figure 3) indicates a 4-fold symmetry but the peak intensity does not allow any conclusions concerning the orthorhombic or tetragonal phase at room temperature.…”

Epitaxial Growth and Electrical Properties of Thick SmSi2 Layers on (001) Silicon

“…The in-plane lattice parameter deduced from the RHEED pattern along the Si[110] azimuth is 4.03 Å , in agreement with the value observed in the high-temperature tetragonal structure of bulk SmSi 2 (4.041 Å ). 22 plane reduces the lattice mismatch from +25.6 to À5:2%, as has also been reported for the growth of orthorhombic GdSi 2 , 23) tetragonal DySi 2 , 17) or hexagonal LuSi 1:7 layers. 18) The lattice parameter variation deduced from the RHEED pattern taken along Si[110] is shown as a function of the growth time in Fig.…”

“…The implied lattice constant along the growth axis is found to be 13.32 Å , in agreement with the expected bulk value of 13.3 Å . 22) The full width at half maximum of the SmSi 2 (004) peak deduced from the XRD rocking curve is about 0.23 . An XRD -scan of the (001) SmSi 2 plane (not shown) indicates a 4-fold symmetry, characteristic of an in-plane cubic structure.…”