Fabrication

About: Fabrication is a research topic. Over the lifetime, 20475 publications have been published within this topic receiving 235676 citations.

Fabrication of Vertical and Uniform-Size Porous InP Structure by Electrochemical Anodization

Abstract: A vertical porous InP structure with an aspect ratio larger than 100 was obtained by electrochemical anodization of a A-oriented n-InP substrate with HCl etchant. The photoluminescence spectrum of this porous InP showed less surface recombination as well as a slight blue shift attributed to the quantum-size effect. By initiating the etching through SiO2-defined mask windows, which were prepared by electron-beam direct writing along 3 crystalline directions, a uniformly sized (around 72% within the permissible fluctuation error of about 4 nm against 100-nm-sized triangles), high-density (around 50%) structure was fabricated for the first time. These results reveal that this process is very attractive for the fabrication of high-density and low-size-fluctuation quantum-wire and -box structures.

Fabrication of silicon nanopillar-based nanocapacitor arrays

Abstract: We report the fabrication of silicon nanopillar-based nanocapacitor arrays using metal-assisted etching in conjunction with electrodeposition. The high aspect ratio made possible by the catalyzed etching provides for an increased effective electrode area and hence a significant improvement in the capacitance density. Electroplated Ni electrode forms a conformal layer over the silicon nanopillars. Capacitance measurements show the expected trend as a function of pillar height and array period. The fabrication approach is simple, compatible with integration into standard silicon technology, and easily scalable.

A low-power CMOS compatible integrated gas sensor using maskless tin oxide sputtering

Abstract: This paper describes a CMOS compatible integrated gas sensor. The device was designed so that the front-end fabrication is fully compatible with the standard CMOS process. The non-CMOS compatible fabrication steps were carried out as post-processing steps. This included the silicon anisotropic etch to create the thermally isolated micro-hotplate (MHP) and the deposition of gas-sensitive thin films using maskless r.f. SnO 2 sputtering. The sensors exhibited high sensitivities to gases, such as ethanol and hydrogen.

Fabrication of High-Density, Large-Area Conducting-Polymer Nanostructures

Abstract: The low-cost, large-scale fabrication of high-density conducting-polymer nanostructures is desirable for a variety of applications. We report the realization of high-density conducting-polymer nanostructures through a combination of nanoimprint lithography, a copolymer strategy, and a lift-off process. Atomic force microscopy and optical measurements reveal that the quality of the prepared structures is rather good, and a resolution of 100 nm is achieved. Electrical measurements show that the conducting-polymer nanowires are conductive and indicate great anisotropy in the parallel and perpendicular directions. Moreover, by further connecting them with larger electrodes, these nanowire arrays function as nanosensors.

Microtip-controlled nanostructure fabrication and multi-tipped field-emission tool for parallel-process nanostructure fabrication

Abstract: Fabrication of crystalline or molecular nanostructures with dimensions less than or equal to 1000Å on a substrate surface is achieved by the indirect and/or direct action of a highly-localized field-emission current, which causes atoms of molecular gases introduced into a vacuum chamber to deposit or etch at surface atomic sites that are fixed by the emission-tip location. The tip is shaped to maintain control of the emitting region and is typically about 10Å above the structure. The tip position is stepped in a programmed sequence, with each step taken on detecting the current increase induced by an atomic deposition below the tip. Gas sequences or mixtures can also be programmed, and microstructures of typically 10 2 -10 8 atoms are thereby formed with exact control of the positions and types of atomic constituents. The multi-tipped tool consists of a large array of field-emitting nanostructure probe tip extensions on the end of a metal probe. The nanostructures are spaced in a prescribed, repeating pattern with typical spacings on the order of 400Å. The probe voltage, current and position, as well as CVD or etching gas pressures, are sequentially adjusted to fabricate nanostructures on a nearby substrate, which is typically 10-30Å below the termination points of the probe tip extensions.