Nec Corporation

National Institute of Advanced Industrial Science and Technology

Other

National Institute for Materials Science

Hidefumi Hiura

Toshihiko Kanayama

Tetsuya Tada

Thomas Ebbesen

Kazuhito Tsukagoshi

Katsumi Tanigaki

Pulickel Madhavapanicker Ajayan

Satoru Toguchi

Fumiyuki Nihei

Hisao Miyazaki

Takehide Miyazaki

Provided is a graphene substrate, which is manufactured by: bringing a metal layer into contact with a carbon-containing layer and heating the metal layer to dissolve carbon in the carbon-containing layer into the metal layer; and cooling the metal layer to precipitate the carbon in the metal layer as graphene on any substrate surface.

Method of manufacturing graphene substrate, and graphene substrate

The invention provides a manufacturing method of a graphene-on-insulator substrate which is mass productive, of high quality, and yet is directly usable for manufacture of semiconductor devices at a low manufacturing cost. According to the manufacturing method of a graphene substrate of the invention, a metal layer and a carbide layer are heated with the metal layer in contact with the carbide layer so that carbon in the carbide layer is dissolved into the metal layer, and then the metal layer and the carbide layer are cooled so that the carbon in the metal layer is segregated as graphene on the surface of the carbide layer.

Manufacturing method of graphene substrate and graphene substrate

Provided is a versatile method of determining the number of layers of a two-dimensional atomic layer thin film as compared with conventional methods. An electron beam is radiated to a two-dimensional thin film atomic structure having an unknown number of layers to determine the number of layers based on an intensity of reflected electrons or secondary electrons generated thereby. In particular, this method is effective for determining the number of layers of graphene.

Method for determining number of layers of two-dimensional thin film atomic structure and device for determining number of layers of two-dimensional thin film atomic structure

A semiconductor graphene is used for a channel layer, and a metal graphene is used for electrode layers for a source, a drain, and a gate which serve as interconnections as well. An oxide is used for a gate insulating layer. The channel layer and the electrode layers are located on the same plane.

Semiconductor device using graphene and method of manufacturing the same

A semiconductor device has a structure in which a light-emitting layer of an organic material or the like is sandwiched between a work function controlled single-wall carbon nanotube cathode encapsulating a donor having a low ionization potential and a work function controlled single-wall carbon nanotube anode encapsulating an acceptor having a high electron affinity. A semiconductor device represented by an organic field-effect light-emitting element and a method of manufacturing the same are provided. The semiconductor device and the method of manufacturing the same make it possible to improve characteristics and performance, such as reduction in light-emission starting voltage and a high luminous efficiency, to improve reliability, such as an increase in life, and to improve productivity, such as reduction in manufacturing cost.

Semiconductor device and method of manufacturing the same

It is to provide a thermodynamically and chemically stable dopant material which can achieve controls of the pn conduction types, carrier density, and threshold value of gate voltage, and a manufacturing method thereof. Further, it is to provide an actually operable semiconductor device such as a transistor with an excellent high-speed operability and high-integration characteristic. Provided is a dopant material obtained by depositing, on a carbon nanotube, a donor with a smaller ionization potential than an intrinsic work function of the carbon nanotube or an acceptor with a larger electron affinity than the intrinsic work function of the carbon nanotube. The ionization potential of the donor in vacuum is desired to be 6.4 eV or less, and the electron affinity of the acceptor in vacuum to be 2.3 eV or more.

Dopant material, dopant material manufacturing method, and semiconductor device using the same

The present invention achieves a shallow junction of a source and a drain, and provides a doping method which makes device properties reproducible and a semiconductor device fabricated using the method. In the present invention, doping for the semiconductor is conducted by attaching a molecular species with a higher electron affinity or lower ionization energy out of fullerene derivatives or metallocenes to the semiconductor surface to induce charge transfer from the molecule to the semiconductor.

Doping method and semiconductor device using the same

A doping method includes the step of attaching molecules or clusters to the surface of a semiconductor substrate to enable charge transfer from the molecules or clusters to the substrate surface, thereby inducing carriers underneath the substrate surface. A semiconductor device is fabricated through attachment of molecules or clusters to the surface of a semiconductor substrate. The attachment enables charge transfer from the molecules or clusters to the substrate surface to induce carriers underneath the substrate surface.

Doping method and semiconductor device fabricated using the method

A carborane supercluster consisting of carborane (C B H ) as its constituent unit expressed as a molecular formula C B H , where x is a positive integer (i.e., x&equals;1, 2, 3, . . . ) and m is an integer greater than unity (i.e., m&equals;2, 3, . . . ). The parameter x represents the count of removed or detached hydrogen atoms. The parameter a represents the count of the clusters linked together. To produce the supercluster, carborane (C B H ) is ionized in a reaction chamber to generate carborane ions and then, the carborane ions thus generated are successively reacted with the remaining neutral (i.e., non-ionized) carborane (C B H ), thereby generating the carborane supercluster. Preferably, the cluster of the carborane consists of at least two of o-carborane, m-carborane, and p-carborane.

Carborane supercluster and method of producing same

A graphite having geometrically shaped holes limited to the top atomic layer such as circles, polygons and combinations thereof, and a method of preparing a graphite having geometrically shaped holes such as circles, polygons and combinations thereof where the geometrically shaped holes are limited to the top atomic layer.

Carbon material and method of preparing the same

A novel carbon material is obtained by bending at least one carbon atom layer of graphite in at least one selected region along either, or both, of lines I and II in FIG. 1. The bending can be accomplished by scanningly picking the carbon atom layer(s) with a probe of an atomic force microscope or another scanning microscope. The obtained carbon material has at least one round bend having a width of 0.1-10 nm and at least one flap region having a triangular, rectangular or still differently polygonal shape in plan view. When the carbon atom layer(s) is bent with very small radii of curvature, a finely striped ridge-and-groove structure appears in the round bend. The physical properties of the obtained carbon material are uniquely determined by the direction(s) of bending, width of each bend, shape and size of each flap region and the stripe pitch of the ridge-and-groove structure.

Carbon material originating from graphite and method of producing same

Disclosed is a process for purifying carbon nanotubes which has steps of 1) mixing carbon nanotubes which accompany carbon impurities with a reagent selected from a group consisting of oxidation agents, nitration agents and sulfonation agents in liquid phase, 2) reacting the carbon nanotubes with the reagent at a predetermined temperature in the liquid phase, wherein the carbon impurities except carbon nanotubes are selectively reacted to dissolve in the liquid phase, and 3) separating carbon nanotubes from which the impurities were released from the liquid phase then washing and drying it. A process for uncapping carbon nanotubes and a process for chemically modifying carbon nanotubes are also disclosed.

Process for purifying, uncapping and chemically modifying carbon

A mixture of carbon nanotubes and impurity carbon materials, which include carbon nanoparticles and may possibly include amorphous carbon, is purified into carbon nanotubes of high purity by utilizing a significant difference in oxidizability between the nanotubes and the nanoparticles. The mixture is pulverized and heated in the presence of an oxidizing agent at a temperature in the range from 600.degree. to 1000.degree. C. until the impurity carbon materials are oxidized and dissipated into gas phase. The nanotubes remain almost unoxidized except for loss of some lengths from the tube tips. It is suitable to perform the heating in air or oxygen.

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Tokyo, Japan

Hidefumi Hiura