Abstract: A magnetic random access memory according to the present invention is provided with: a magnetic recording layer including a magnetization free region having a reversible magnetization, wherein a write current is flown through the magnetic recording layer in an in-plane direction; a magnetization fixed layer having a fixed magnetization; a non-magnetic layer provided between the magnetization free region and the magnetization fixed layer; and a heat sink structure provided to be opposed to the magnetic recording layer and having a function of receiving and radiating heat generated in the magnetic recording layer. The magnetic random access memory thus-structured radiates heat generated in the magnetic recording layer by using the heat sink structure, suppressing the temperature increase caused by the write current flown in the in-plane direction.

Abstract: A carbon nanotube dispersion liquid obtained by mixing carbon nanotubes, a first organic solvent that is a nonpolar solvent, and a second organic solvent that has a polarity higher than that of this first organic solvent and is compatible with this first organic solvent.

Abstract: A problem of a switching element using for the active layer a carbon nanotube (CNT) dispersion film that can be manufactured at low temperature has been that sufficient electrical contact and thermal conductivity between the CNTs and the source and drain electrode surfaces are not obtained. The switching element of the present invention has a structure in which a mixed layer of carbon nanotubes and a metal material, and a metal layer of the metal material are laminated in this order on source and drain electrodes, and thereby, the CNT-dispersed film and the electrode surfaces can be in firm electrical, mechanical, and thermal contact with each other. Thus, a switching element exhibiting good and stable transistor characteristics is obtained with a low-temperature, convenient, and low-cost process.

Abstract: This invention provides a semiconductor element which uses a plurality of carbon nanotubes as a current path, can reduce contact resistance of its electrode contact part, and has excellent electrical characteristics. This semiconductor element is characterized in that the semiconductor element includes a current path (16) comprised of a plurality of carbon nanotubes (18) and not less than two electrodes (14, 15) connected with the current path, wherein at least one or more of the electrodes is made of a mixture of a metal and a carbon material (17) having SP2 hybridized orbital, such as a multi-walled carbon nanotube, a glassy carbon, and graphite particles.

Abstract: A magnetic memory cell 1 is provided with a magnetic recording layer 10 which is a ferromagnetic layer and a pinned layer 30 connected with the magnetic recording layer 10 through a non-magnetic layer 20. The magnetic recording layer 10 has a magnetization inversion region 13, a first magnetization fixed region 11 and a second magnetization fixed region 12. The magnetization inversion region 13 has a magnetization whose orientation is invertible and overlaps the pinned layer 30. The first magnetization fixed region 11 is connected with a first boundary B1 in the magnetization inversion region 13 and a magnetization orientation is fixed on a first direction. The second magnetization fixed region 12 is connected with a second boundary B2 in magnetization inversion region 13 and a magnetization orientation is fixed on a second direction. The first direction and the second direction are opposite to each other.

Abstract: A magnetic recording layer 10 of an MRAM has a first magnetization fixed region 11, a second magnetization fixed region 12 and a magnetization switching region 13. The magnetization switching region 13 has reversible magnetization and overlaps with a pinned layer. The first magnetization fixed region 11 is connected to a first boundary B1 of the magnetization switching region 13 and its magnetization direction is fixed to a first direction. The second magnetization fixed region 12 is connected to a second boundary B2 of the magnetization switching region 13 and its magnetization direction is fixed to a second direction. Both of the first direction and the second direction are toward the magnetization switching region 13 or away from the magnetization switching region 13. The damping coefficient ? in at least a portion R1, R2 of the magnetization fixed regions 11 and 12 is larger than the damping coefficient ? in the magnetization switching region 13.

Abstract: An end portion (104a) of a first source electrode (104) and an end portion (105a) of a first drain electrode (105) face each other on a gate insulating film (103) via a channel formation region. The first source electrode (104) and first drain electrode (105) extend over steps, and the end portion (104a) and end portion (105a) face each other on the gate insulating film (103). The highest portions of the end portion (104a) and end portion (105a) are formed higher than the upper surface of the gate insulating film (103) serving as the channel formation region. A field-effect transistor of this invention also includes a second source electrode (107) which is formed in contact with the channel layer (106) and connects the first source electrode (104) and channel layer (106), and a second drain electrode (108) which is formed in contact with the channel layer (106) and connects, the first drain electrode (105) and channel layer (106).

Abstract: The present invention provides a new data writing method for an MRAM which can suppress deterioration of a tunnel barrier layer. A magnetic memory cell 1 has a magnetic recording layer 10 and a pinned layer 30 connected to the magnetic recording layer 10 through a non-magnetic layer 20. The magnetic recording layer 10 includes a magnetization switching region 13, a first magnetization fixed region 11 and a second magnetization fixed region 12. The magnetization switching region 13 has reversible magnetization and faces the pinned layer 30. The first magnetization fixed region 11 is connected to a first boundary B1 of the magnetization switching region 13 and its magnetization direction is fixed to a first direction. The second magnetization fixed region 12 is connected to a second boundary B2 of the magnetization switching region 13 and its magnetization direction is fixed to a second direction.

Abstract: This invention provides a semiconductor element which uses a plurality of carbon nanotubes as a current path, can reduce contact resistance of its electrode contact part, and has excellent electrical characteristics. This semiconductor element is characterized in that the semiconductor element includes a current path (16) comprised of a plurality of carbon nanotubes (18) and not less than two electrodes (14, 15) connected with the current path, wherein at least one or more of the electrodes is made of a mixture of a metal and a carbon material (17) having SP2 hybridized orbital, such as a multi-walled carbon nanotube, a glassy carbon, and graphite particles.

Abstract: When an electronic element using a carbon nanotube (CNT) is fabricated, particularly when a carbon nanotube thin film is formed on a previously formed electrode, a CNT film is manufactured on the previously formed electrode, and the CNT film on the electrode is used as an electronic element, as it is. In this case, a problem is that unless the carbon nanotubes and the electrode are in sufficient contact with each other, the contact resistance increases, and sufficient element properties are not obtained. When a carbon nanotube thin film is formed on a previously formed electrode, a conductive organic polymer thin film is formed, before or after the carbon nanotube thin film is manufactured, to decrease the contact resistance.

Abstract: A problem of a switching element using for the active layer a carbon nanotube (CNT) dispersion film that can be manufactured at low temperature has been that sufficient electrical contact and thermal conductivity between the CNTs and the source and drain electrode surfaces are not obtained. The switching element of the present invention has a structure in which a mixed layer of carbon nanotubes and a metal material, and a metal layer of the metal material are laminated in this order on source and drain electrodes, and thereby, the CNT-dispersed film and the electrode surfaces can be in firm electrical, mechanical, and thermal contact with each other. Thus, a switching element exhibiting good and stable transistor characteristics is obtained with a low-temperature, convenient, and low-cost process.

Abstract: A magnetic random access memory comprises a magnetic recording layer equipped with a magnetization reversal region having a reversible magnetization and through which a write current is made to flow in the in-plane direction, a magnetization fixed layer having a fixed magnetization, a nonmagnetic layer provided between the magnetization reversal region and the magnetization fixed layer, and a heat absorbing structure provided opposing to the magnetic recording layer and having a function of receiving heat generated in the magnetic recording layer and of radiating the heat. Such magnetic random access memory can radiate heat generated in the magnetic recording layer by using the heat absorbing structure and prevent temperature rising caused by the write current flowing in the in-plane direction.

Abstract: The present invention provides a new data writing method for an MRAM which can suppress deterioration of a tunnel barrier layer. A magnetic memory cell 1 has a magnetic recording layer 10 and a pinned layer 30 connected to the magnetic recording layer 10 through a non-magnetic layer 20. The magnetic recording layer 10 includes a magnetization switching region 13, a first magnetization fixed region 11 and a second magnetization fixed region 12. The magnetization switching region 13 has reversible magnetization and faces the pinned layer 30. The first magnetization fixed region 11 is connected to a first boundary B1 of the magnetization switching region 13 and its magnetization direction is fixed to a first direction. The second magnetization fixed region 12 is connected to a second boundary B2 of the magnetization switching region 13 and its magnetization direction is fixed to a second direction.

Abstract: A magnetic recording layer 10 of an MRAM has a first magnetization fixed region 11, a second magnetization fixed region 12 and a magnetization switching region 13. The magnetization switching region 13 has reversible magnetization and overlaps with a pinned layer. The first magnetization fixed region 11 is connected to a first boundary B1 of the magnetization switching region 13 and its magnetization direction is fixed to a first direction. The second magnetization fixed region 12 is connected to a second boundary B2 of the magnetization switching region 13 and its magnetization direction is fixed to a second direction. Both of the first direction and the second direction are toward the magnetization switching region 13 or away from the magnetization switching region 13. The damping coefficient ? in at least a portion R1, R2 of the magnetization fixed regions 11 and 12 is larger than the damping coefficient ? in the magnetization switching region 13.

Abstract: A magnetic memory cell 1 is provided with a magnetic recording layer 10 which is a ferromagnetic layer and a pinned layer 30 connected with the magnetic recording layer 10 through a non-magnetic layer 20. The magnetic recording layer 10 has a magnetization inversion region 13, a first magnetization fixed region 11 and a second magnetization fixed region 12. The magnetization inversion region 13 has a magnetization whose orientation is invertible and overlaps the pinned layer 30. The first magnetization fixed region 11 is connected with a first boundary B1 in the magnetization inversion region 13 and a magnetization orientation is fixed on a first direction. The second magnetization fixed region 12 is connected with a second boundary B2 in magnetization inversion region 13 and a magnetization orientation is fixed on a second direction. The first direction and the second direction are opposite to each other.

Abstract: A technology for eliminating the defects in a tunnel insulation film of magnetic tunnel junction and for suppressing generation of a defective bit in an MRAM using magnetic tunnel junction in a memory. The magnetic memory includes a substrate, an interlayer insulation film covering the upper surface side of the substrate, memory cells, and plugs penetrating the interlayer insulation film. The memory cell includes a first magnetic layer formed on the upper surface side of the interlayer insulation film, a tunnel insulation layer formed on the first magnetic layer, and a second magnetic layer formed on the tunnel insulation layer. The plug is connected electrically with the first magnetic layer. The tunnel current passing part of the tunnel insulation layer located between the first and second magnetic layers is arranged, at least partially, so as not to overlap the plug in the direction perpendicular to the surface of the substrate.

Abstract: A technique is provided in which an offset magnetic field of a memory cell of a MRAM is reduced more effectively. The MRAM of the present invention is composed of a free layer (11) which has a reversible free spontaneous magnetization, a fixed layer (6) which has fixed spontaneous magnetization, and a spacer layer (10) formed of non-magnetic interposed between the free layer (11) and the fixed layer (6). The fixed layer (6) is formed such that orange peel effect and magneto-static coupling effect does not substantially influence on the free layer (11).

Abstract: A technology for eliminating the defects in a tunnel insulation film of magnetic tunnel junction and for suppressing generation of a defective bit in an MRAM using magnetic tunnel junction in a memory. The magnetic memory includes a substrate, an interlayer insulation film covering the upper surface side of the substrate, memory cells, and plugs penetrating the interlayer insulation film. The memory cell includes a first magnetic layer formed on the upper surface side of the interlayer insulation film, a tunnel insulation layer formed on the first magnetic layer, and a second magnetic layer formed on the tunnel insulation layer. The plug is connected electrically with the first magnetic layer. The tunnel current passing part of the tunnel insulation layer located between the first and second magnetic layers is arranged, at least partially, so as not to overlap the plug in the direction perpendicular to the surface of the substrate.

Abstract: A technique is provided in which an offset magnetic field of a memory cell of a MRAM is reduced more effectively. The MRAM of the present invention is composed of a free layer (11) which has a reversible free spontaneous magnetization, a fixed layer (6) which has fixed spontaneous magnetization, and a spacer layer (10) formed of non-magnetic interposed between the free layer (11) and the fixed layer (6). The fixed layer (6) is formed such that orange peel effect and magneto-static coupling effect does not substantially influence on the free layer (11).

Abstract: A method of manufacturing a magnetic random access memory for excluding stress-induced defects in memory cells. The method is composed of forming a first magnetic film over a substrate, forming a tunnel insulating film on the first magnetic film such that the tunnel insulating film has a curvature, forming a second magnetic film on the tunnel insulating film, and etching the first magnetic film, the tunnel insulating film and the second magnetic film to form a memory cell. The etching is executed such that the curvature is excluded from the memory cell.