To fabricate OICR-9429 nmr CNT-based two-terminal devices using our approach, horizontal alignment of CNTs might be necessary,
and the orientation of CNTs could be aligned to the applied electric field [45], magnetic field [46], and direction of gas flow [47]. Nanostencil lithography could be extended to control the number of various one-dimensional nanomaterials that are grown and the specific sites where they are grown by depositing other catalysts such as gold for silicon, gallium nitride, or zinc oxide nanowires. Since these one-dimensional nanomaterials have unique characteristic, for example, ZnO nanowire array exhibits giant optical anisotropy due to high aspect ratio, subwavelength diameter, and high permittivity [48], the proposed position- and number-controlled synthesis approach could be useful to realize nanomaterial-based devices with enhanced functionalities and mass producibility. Figure 4 Number-controlled growth of CNTs by using apertures with different diameters. (a, b) SIM images of 21 × 21 nanoapertures in a stencil mask consisting of 140-nm-diameter apertures and 10-μm spacing between each aperture. The inset in (b) shows an enlarged view of the aperture shown
in (a). (c, d, e) SEM images of CNTs synthesized using apertures of various diameters. Some CNTs (c), mainly double CNTs (d), and individual CNT (e) were synthesized through apertures whose see more diameters were 140, 80, and 40 nm, respectively. The insets show the apertures used to synthesize CNTs. (f) The number of CNTs synthesized
was strongly dependent on the diameter of the nanostencil aperture. Yield was 39.6% for individual CNTs synthesized using 40-nm-diameter aperture. Conclusions We fabricated stencil masks containing nanoaperture arrays down to 40 nm in diameter in order to characterize the relation between the size of the patterned catalyst and the number of CNTs that were subsequently synthesized on the catalyst. The nanostencil Fossariinae mask was fabricated by first forming a low-stress DNA Damage inhibitor silicon nitride membrane on a silicon substrate. FIB milling was subsequently used to generate nanoapertures on the membrane. The iron catalyst used to synthesize the CNTs was then deposited through the nanoapertures onto the silicon substrate. The diameter of iron catalyst was larger than that of the aperture because of blurring, and the thickness of the catalyst decreased with decreasing aperture diameter. Accordingly, the number of CNTs could be controlled by controlling the diameter of the aperture, and the iron catalyst patterned with the 40-nm-diameter aperture on the stencil mask was used to synthesize an individual CNT at the desired sites. The demonstrated scalable, number- and location-controlled synthesis of CNTs is potentially applicable to massively parallel integration of single CNTs on each of the desired locations and may enhance the producibility and yield of CNT-based functional devices.