Growth of Metal Nanowhiskers on Patterned Substrate by High Temperature Glancing Angle Deposition

Abstract

In this study, we carry out high temperature glancing angle deposition (HT-GLAD) of Fe and Al on a heated substrate with trench patterns. When vapor is incident perpendicular to the trench direction, nanowhiskers grow only on the surface exposed to the vapor and not inside the trenches. When vapor is incident at a deposition angle larger than 80° on the sidewall of the trench and not on the substrate surface, nanowhiskers grow only on the sidewall because the condition of deposition at a high temperature and a large deposition angle is satisfied only for the sidewall. Thus, we succeed in the selective growth of nanowhiskers by controlling the geometrical deposition conditions. Further, we also discuss the effect of the local deposition geometry on the growth process.Geometrically selective growth by HT-GLAD is expected to be useful for growing nanowhiskers on nano-and microstructured substrates.

Thermochromic VO2 nanorods made by sputter deposition: Growth conditions and optical modeling

“…[154][155][156][157][158] For the case of metal nanowires, the substrate temperature should be higher than about one third of the metal's melting point and the deposition angle typically should exceed 80° with regard to the substrate normal. For the VO 2 nanowires in the present study, we expect that the relative magnitude of the fluxes of vanadium atoms and oxygen molecules plays a decisive role.…”

Stress-induced growth of aluminum nanowires with a range of cross-sections

“…To date, Al nanostructures (e.g., 2D nanopatterns and 1D nanowires (NWs), and nanotubes (NTs)) are mainly fabricated by top‐down lithographic methods, including electron beam lithography (EBL), nanosphere lithography (NSL), and anodized aluminum oxide (AAO) template lithography . For bottom‐up, self‐assembled growth, wet chemical methods are restricted to the fabrication of noble metal (e.g., Au, Ag, Pt) nanostructures , though there have been reports of stress‐induced , electromigration‐induced and vapor‐phase growth in glancing angle deposition of Al microwires and nanowires. The advantages of bottom‐up growth of Al nanostructures are ultra‐smoothness and the possibility in formation of 3D structures.…”

“…The advantages of bottom‐up growth of Al nanostructures are ultra‐smoothness and the possibility in formation of 3D structures. Existing bottom‐up techniques for Al nanostructures are still in the early development stage, requiring improvements in achieving higher yields, controlling growth conditions and reaching smaller dimensions .…”

Temperature threshold for nanorod structuring of metal and oxide films grown by glancing angle deposition

“…For the experimental conditions used in the present study, nanorod structuring on room temperature substrates occurs for materials with melting points higher than that of Al ͑933 K͒. It has been reported that GLAD-grown Al, 30,31 Fe, 31 and Ag 32 films have isolated nanowhiskers on planar morphologies when grown by electron beam evaporation or ion beam deposition at elevated temperatures, but such flat film morphologies containing only a few isolated nanowhiskers do not fall into our definition of a nanorod structured film and thus should not be compared with the film types reported in the present study.…”