Shape Transition in the Initial Growth of Titanium Silicide Clusters on Si(111)

Abstract

The growth of titanium silicide clusters has been observed for sub-monolayer Ti deposited on Si(111)-7 Â 7. Irregular shape tetragonal Ti 5 Si 4 islands were observed to grow at 600 C. On the other hand, the elongated orthorhombic-Ti 5 Si 4 (O-Ti 5 Si 4 Þ clusters form at 700 C. The clusters underwent a rapid increase in length and slight reduction in width as the cluster area exceeds a critical size ($15 nm 2 Þ. The elongated clusters are oriented along three equivalent Sih2-20i directions of the Si(111) surface with O-Ti 5 Si 4 (025)==Si(2-20). The shape change is in agreement with theoretical prediction based on the strain relief mechanism.

Formation of Epitaxial NiSi<SUB>2</SUB> Nanowires on Si(100) Surface by Atomic Force Microscope Nanolithography

“…4(b) and (e)). The faceted edges of the square silicide nanodots were parallel to the Si 110 direction, as observed by Chen et al 20 and Cheng et al 21 22 The square silicide nanodots were identified as epitaxial (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). Upon annealing at 600 C, the morphology of silicide nanoparticles was close to spherical, as shown in Figures 4(c and f).…”

“…3 In recent years, epitaxial silicide nanowires have been formed on Si substrate by self-assembled growth. [4][5][6][7][8][9][10][11][12][13] The epitaxial growth of silicide on Si substrate is a requisite property for the formation of nanowires. Thus, the only silicide nanowires with a specific phase and orientation can be obtained.…”

Controlled growth of the silicide nanostructures on Si bicrystal nanotemplate at a precision of a few nanometres

“…On the other hand, orthorhombic and tetragonal Ti 5 Si 4 may coexist at 700 C if the amount of deposited Ti is low. 22 It was previously found that the decrease in film thickness would result in the increase of the formation temperature of C49-TiSi 2 . 23…”

Metal silicides: An integral part of microelectronics

“…40 It is, however, interesting that TiSi 2 nanowires are incommensurate (8%) in their long direction. 46 However, the interface structure for the nanowires may not be the same as that inferred from the bulk lattices.…”