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AssigneesCovalent Materials Corporation, Techno Network Shikoku Co., Ltd.
InventorsAkitmitsu Hatta, Hiroaki Yoshimura, Keiichi Ishimoto, Hiroaki Kanakusa, Shinichi Kawagoe
Estimating the term…
By uniformly forming an indefinite number of microscopic acicular crystals on a surface of a silicon substrate so as to be perpendicular to the surface of the substrate by plasma CVD method using a catalyst, it is possible to reliably, homogeneously and massively form an ultramicroscopic acicular silicon crystal having a substantial cone shape tapered so as to have a radius of curvature of not less than 1 nm to no more than 20 nm at its tip end and having a diameter of bottom surface of not less than 10 nm, and a height equivalent to or more than the diameter of bottom surface, at a desired location.
A method for producing an acicular silicon crystal which comprises:
Dependencies are inferred from the claim text.
Drawings are temporarily unavailable. Open the PDF at USPTO
From the US filing history. Foreign family members aren’t listed.
Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth: growth of whiskers or needles
Elements: silicon
Single-crystal, oriented-crystal, and epitaxy growth processes; non-coating apparatus therefor: dendrite or web or cage technique
Stock material or miscellaneous articles: self-sustaining carbon mass or layer with impregnant or other layer
Term ended 5 May 2024 (estimated)
The present invention relates to acicular silicon crystals and methods for producing thereof, and more specifically, to a nano-sized silicon acicular crystal having a sharp-pointed shape which is useful in nanotechnology, and to a method enabling mass formation of the acicular silicon crystal on a silicon substrate.
With the recent sophistication in technologies of electronics industries, demands for more miniaturized and integrated devices are increasing. The miniaturization degree in the process technologies have now exceeded the ranges of sub micrometers to reach the order of nanometer(nm). For this reason, devices or components of several tens of nanometers to several nanometers in size are required.
As a microscopic material for producing such components or devices, a carbon nano tube discovered in 1991 is attracting the attention.
FIG. 1 is an electron microscopic picture of an acicular silicon crystal according to the present invention.
FIG. 2 is an electron microscopic picture of a group of acicular silicon crystals formed on a silicon substrate according to the present invention.
FIG. 3 is a schematic section view showing a direct-current sputtering step in which a catalytic metal (iron wire) is used as an electrode in the production method according to the present invention.
The present invention will be now explained more detail partly with reference to the attached drawings.
FIG. 1 is an electron microscopic picture of an acicular silicon crystal according to the present invention.
As shown in FIG. 1, an acicular silicon crystal 1 according to the present invention is tapered to have a radius of curvature of nano order at its tip end, and has a vertically long, substantially conical shape in which a ratio of height to diameter of bottom surface is not less than one.