Suspended nanostructures grown by electron beam-induced deposition of Pt and TEOS precursors

Abstract

Suspended nanostructures (SNSs) are grown by electron beam-induced deposition (EBID) of Pt and tetra-ethyl-ortho-silicate (TEOS) gas precursors on nanopillar tips, by lateral shifting of a scanning electron microscope beam. Shape evolution of SNSs is characterized as a function of electron energy (5, 10, 15 keV) and electron charge deposited per unit length (CDL, 1–9 pC nm−1 range) along the beam track. Pt SNSs grow as single nanowires, evolving from thin (15–20 nm) and horizontal to thick (up to 70 nm) and inclined (up to 60°) geometry as CDL increases. TEOS SNSs consist of multiple nanowires arranged in a stack: horizontal and parallel along the beam shift direction and aligned on top of each other along the beam incidence axis. As the CDL increases, the number of nanowires increases and the top edge of the stack progressively inclines, taking the form of a hand-fan. Deposition yield and overall size of SNSs are found to be proportional to CDL and inversely proportional to electron energy for both Pt and TEOS precursors. As an example of 3D nanoarchitectures achievable by this lateral EBID approach, a ‘nano-windmill’ TEOS structure is presented.

Three dimensional magnetic nanowires grown by focused electron-beam induced deposition

“…They are 4–12 μm long, with a circular cross section (see figure 1(c)), and diameters Ø = 100 ± 25 nm. The NWs can be fabricated at any angle with respect to the substrate plane18. For these dimensions, after optimising growth parameters such as roughness, purity, homogeneity and minimum residual parasitic deposit, we obtained NWs with approximately 85% cobalt content, with the rest being carbon and oxygen.…”

Structural evolution and graphitization of metallorganic-Pt suspended nanowires under high-current-density electrical test

“…EBID, in particular, has found growing utilization because of its increased availability on scanning electron microscope ͑SEM͒ and transmission electron microscope ͑TEM͒ and on recent electron-beam lithography systems, and because it avoids the ion-damage effects of IBID. Depositions are usually performed on a substrate, but self-standing suspended deposition can be obtained by slowly moving the beam laterally from an elevated edge, 3 with the advantages of enabling a higher spatial resolution and a three-dimensional nanofabrication. This latter is an interesting perspective, as demonstrated by the variety of nanodevices based on suspended architectures 4,5 recently proposed.…”

Helium ion beam induced growth of hammerhead AFM probes

“…Apparently, the amount of deposited material progressively reduces while the horizontal beam shift proceeds. 16 At some point, the beam shift outruns the precursor supply and the growth stops. As a result, the final needle is shorter than designed (l < L); see (3) in Fig.…”