Surface Cleanness Dependence of the Interfacial Orientation of Endotaxial NiSi[sub 2] on Si(001)

Abstract

In the growth of endotaxial nickel disilicide on Si͑001͒ using reactive deposition epitaxy, three types of structures, which include the inverted-hut structure containing only the A-type NiSi 2 /Si interfaces, the parallel-epipedal structure, and the nanowire structure containing the B-type NiSi 2 /Si interfaces, can be observed. In this paper, we show that the formation of both the nanowires and the parallel-epipedal structures is related to the substrate surface-cleaning process and deposition temperatures. The formation of both the nanowires and the parallel-epipedal structures can be suppressed either with the high surface-cleaning temperature or at the low Ni deposition temperature.

Formation of nanoflowers: Au and Ni silicide cores surrounded by SiOx branches

“…A number of works about self-assembled epitaxial Ni silicide have been published [ 41 – 46 ], and some works pointed out that the Ni 2 Si phase formed first, followed by NiSi and NiSi 2 after annealing [ 47 – 49 ]. Generally, NiSi 2 forms above 600 °C [ 42 – 45 48 ]. Therefore, the self-assembled epitaxial line structures in this work are supposed to be NiSi 2 .…”

Shape-Controlled Fabrication of Micro/Nanoscale Triangle, Square, Wire-like, and Hexagon Pits on Silicon Substrates Induced by Anisotropic Diffusion and Silicide Sublimation

“…Propelled by the motivations delineated in the previous paragraph, there has been intensive interest in understanding the reactions between silicon and metals, especially the formation of silicides. − Among metal silicides, cobalt silicides possess very interesting and important properties, which has invited many research efforts, both fundamental and application-oriented. Cobalt disilicide (CoSi 2 ) is widely used as a primary contact material in the metallization of Si-based integrated circuits, owing to its low resistivity (15−20 μohm·cm), low processing temperature, and good thermal stability. , There has been lots of research on the Si−Co systems, in particular on the issues of silicide formation, stability, and electrical transport. − For example, van Gurp and Langereis synthesized cobalt silicide layers by depositing Co onto Si wafers with subsequent thermal treatment and studied the Co diffusion in the silicide growth process .…”