Abstract: The present invention relates to a thin-film transistor (TFT) active device. The TFT active device includes: a gate electrode; a gate insulation layer covering the gate electrode; an oxide semiconductor layer formed on the gate insulation layer; a first protection layer formed on the oxide semiconductor layer; a source/drain electrode electrically connected with the oxide semiconductor layer; and a second protection layer covering the source/drain electrode. At least one of the gate insulation layer, the first protection layer, and the second protection layer is made of a nitride of silicon and has a refractive index between 2.0-3.0. The TFT active device according to the present invention helps suppressing diffusion of metal ions from a metal electrode and reducing hydrogen content of the GI layer, the ES layer, or the PV layer so as to effectively improve the stability of the manufacture operation of TFT.

Abstract: A method for recording to and reproducing from a magnetic recording medium is disclosed in which an information signal is recorded and reproduced under thermal assist, and which allows one to stably record tiny recording magnetic domains and stably detect a reproduction output signal during reproduction when recording at high density. In this method, the temperature distribution in the information recording and reproduction region of the magnetic recording medium is controlled to be different during recording and during reproduction. This allows recording magnetic domains to be stabilized even when recording fine marks, and greatly increases the recording density because stable detection is possible without reducing the reproduction signal amplitude.

Abstract: A method is disclosed to transfer information from a first information storage and retrieval system to a second information storage and retrieval system. The method provides a first information storage and retrieval system comprising a first track size and a plurality of first tracks, and a second information storage and retrieval system comprising a second track size and a plurality of second tracks. The method determines if the first track size is greater than the second track size. If the method determines that the first track size is greater than said second track size, then the method sets a ratio (R) equal to the first track size divided by the second track size, provides the (i)th first track from the first information storage and retrieval system to the second information storage and retrieval system, provides (R) second tracks, and maps the (i)th first track onto the (R) second tracks.

Abstract: A method and apparatus for controlling read-out and/or synchronization between an external magnetic field and written data during a reading operation from a magneto-optical recording medium includes generating a pulse in a reading signal in a read-out layer by copying a mark region from a storage layer to the read-out layer upon heating by a radiation power and with the aid of the external magnetic field. The waveform of the reading signal is analyzed, and the analysis result is used for correcting a phase deviation and/or for controlling a copy window size of the mark copying. Phase errors may thus be corrected for any size of the copy window. Even small changes in the copy window can be detected and corrected.

Abstract: Provided is a magneto-optical recording medium capable of accurately reproducing a signal of a recording density exceeding a resolution of an optical system without making a constitution thereof complicated. The magnetic domain wall displacement type magneto-optical recording medium, comprises: a magnetic domain wall displacement layer in which a magnetic domain wall moves to contribute to information reproduction; a memory layer holding a recorded magnetic domain corresponding to the information; and a switching layer which is arranged between the magnetic domain wall displacement layer and the memory layer and has a Curie temperature lower than Curie temperatures of the magnetic domain wall displacement layer and the memory layer.

Abstract: A domain-wall-displacement-type magnetooptical recording medium is provided in which a floating magnetic field from a surrounding portion that operates on a recording/reproducing portion is suppressed. The recording medium includes a displacement layer having a composition such that rare-earth-element sub-lattice magnetization is dominant at room temperature, a switching layer, a memory layer, and a magnetization compensation layer in which iron-family-element sub-lattice magnetization is dominant at room temperature, for suppressing generation of a stray magnetic field at a temperature near room temperature.

Abstract: A magneto-optical recording medium includes a substrate and a reproducing layer and a recording layer provided on the substrate. A recording magnetic domain is provided in the recording layer by heating the recording layer by irradiation with light and applying a recording magnetic field to the recording layer in such a manner that information is recorded in the recording layer. The recording layer is a magnetic film having magnetic anisotropy in a direction perpendicular to the film surface, and the magnetic film holds the recording magnetic domain formed therein. The magneto-optical recording medium further comprises a intermediate layer and a reproducing aid layer between the reproducing layer and the recording layer. Saturated magnetization of the reproducing aid layer increases with an increase in the temperature of the reproducing aid layer.

Abstract: A magneto-optical recording medium, including a recording layer, a transfer control layer magnetically coupled to the recording layer, and a reproduction layer. The recording layer includes a recording magnetic domain in which information is recorded by a magnetization direction vertical to the surface of the film. The reproduction layer includes a reproduction magnetic domain in which information in the recording layer is transferred and formed as a magnetization direction by magnetic coupling. The direction of magnetization of the recording magnetic domain of the recording layer and the direction of magnetization of the transfer control layer corresponding to the recording magnetic domain are in opposite directions in at least part of the range of temperatures less than a transfer temperature where the reproduction magnetic domain is transferred to the reproduction layer. The Curie point temperature of the transfer control layer is higher than this transfer temperature.

Abstract: In a magneto-optical recording medium, a first magnetic layer is made of a material using a Gd—Fe film or a Gd—Fe—Co film as a base so that a magnetic field normalized based on saturation magnetization of a magnetic domain wall driving field can be smaller than 1. A second magnetic layer is made of a material using a Tb—Fe film or a Dy—Fe film as a base, to which a nonmagnetic element such as Al or Cr, and Co are added. A third magnetic layer is made of a material using a Tb—Fe—Co film or a Dy—Fe—Co film as a base, and an element concentration ratio (at. % ratio) of Tb or Dy to Fe—Co is set in a range of 24.5?Tb?26.5 or 26.5?Dy?29.5. Addition amounts of Co and a nonmagnetic element to each magnetic layer are adjusted to set Curie temperatures Tc11, Tc12, and Tc13 of the first, second and third magnetic layers to Tc13>Tc11>Tc12.

Abstract: In a magneto-optical recording medium, a first magnetic layer is made of a material using a Gd—Fe film or a Gd—Fe—Co film as a base so that a magnetic field normalized based on saturation magnetization of a magnetic domain wall driving field can be larger than 1, and an element concentration ratio (at. % ratio) of Gd to Fe or Fe—Co is set in a range of 28.0?Gd?29.0. A second magnetic layer is made of a material using a Tb—Fe film or a Dy—Fe film as a base, to which a nonmagnetic element such as Al or Cr, and Co are added. A third magnetic layer is made of a material using a Tb—Fe—Co film or a Dy—Fe—Co film as a base, and an element concentration ratio (at. % ratio) of Tb or Dy to Fe—Co is set in a range of 23.5?Tb?25.5 or 25.5?Dy?28.5.

Abstract: A magneto-optical recording/reproducing method is disclosed which causes a laser beam to be emitted to a disc recording medium having information recorded thereon earlier by magnetic field modulation, the laser beam causing the disc recording medium to develop a temperature distribution such as to generate a driving force for moving a domain wall of a magnetic domain in the medium so that the magnetic domain smaller in diameter than a spot of the laser beam is expanded sufficiently to let information recorded in the domain be detected. The method comprises the steps of: recording information to the disc recording medium while rotating the medium in a first rotating direction; and reproducing the information that was recorded to the disc recording medium in the recording step while rotating the medium in a second rotating direction reverse to the first rotating direction.

Abstract: A magneto-optical recording medium has magneto-optical recording layers (11, 12, 13) and reproducing layers (21, 22, 23). The information recorded in the reproducing layers are reproduced by means of reproducing light beams (31, 32, 33) of different wavelengths, respectively. In reproduction, magnetic domains (4) recorded in the recording layers are transferred in the reproducing layers formed on the respective recording layers, the transferred magnetic domains (5) are enlarged with an external magnetic field, and the information is reproduced. Since information is recorded and reproduced for each recording layer, the recording density is improved. Further since the reproduction signals are amplified by the magnetic domain enlargement, the C/N is improved.

Abstract: A magneto-optical recording medium includes a substrate and a reproducing layer and a recording layer provided on the substrate. A recording magnetic domain is provided in the recording layer by heating the recording layer by irradiation with light and applying a recording magnetic field to the recording layer so that information is recorded in the recording layer. The recording layer is a magnetic film having magnetic anisotropy in a direction perpendicular to the film surface, and the magnetic film holds the recording magnetic domain formed therein.

Abstract: A magneto-optical medium of a domain wall displacement type is provided which does not cause inward leakage of signals caused by domain wall displacement from the rear of a reproducing light spot. The magneto-optical medium comprises a domain wall displacement layer, a switching layer, and a memory layer. The switching layer has a boundary temperature higher than room temperature for transformation from a state of a perpendicular magnetization film to a state of an in-plane magnetization film.

Abstract: A magneto-optical recording medium, including a recording layer, a transfer control layer magnetically coupled to the recording layer, and a reproduction layer. The recording layer includes a recording magnetic domain in which information is recorded by a magnetization direction vertical to the surface of the film. The reproduction layer includes a reproduction magnetic domain in which information in the recording layer is transferred and formed as a magnetization direction by magnetic coupling. The direction of magnetization of the recording magnetic domain of the recording layer and the direction of magnetization of the transfer control layer corresponding to the recording magnetic domain are in opposite directions in at least part of the range of temperatures less than a transfer temperature where the reproduction magnetic domain is transferred to the reproduction layer. The Curie point temperature of the transfer control layer is higher than this transfer temperature.

Abstract: A magneto-optical recording medium includes a substrate and a reproducing layer and a recording layer provided on the substrate. A method for reproducing information from the magneto-optical recording medium includes increasing the temperature of the magneto-optical recording medium irradiated by laser light and included in an inside part of a light spot to a temperature range including a temperature at which the saturated magnetization of at least the recording layer or the reproducing aid layer is maximized, and reproducing the information only from a temperature region within the light spot where the information can be transcribed from the recording layer by a magnetic coupling force between the recording layer and the reproducing layer, by transcribing the recording magnetic domain from the recording layer onto the reproducing layer.

Abstract: A magneto-optical storage medium includes an interference layer, a magnetic domain expansion layer, an intermediate layer, a magnetic masking layer, a recording layer, and a protection layer which are sequentially formed on a substrate. The magnetic domain expansion layer produces a smaller frictional force due to wall coercivity than do the other magnetic layers. The intermediate layer has the Curie temperature TC2 which is lower than those of the other magnetic layers. The magnetic masking layer is in a perpendicular magnetization state at temperatures that are in a proximity of TC2, and changes into an in-plane magnetization state at temperatures that are higher than the proximity of TC2. The recording layer produces a higher coercive force than those produced by the magnetic domain expansion layer at room temperature.

Abstract: A magneto-optic recording medium in which information is reproduced while a recording magnetic domain is enlarged by displacing a domain wall based on a temperature distribution formed by a beam of light and having a maximum temperature Tr. The recording medium comprises a reproducing layer in which a domain wall is displaced, a recording layer for holding a recording magnetic domain corresponding to information, and a cutoff layer disposed between the reproducing layer and the recording layer and having a Curie temperature lower than those of the reproducing layer and recording layer. The recording medium satisfies the following condition; (Tr−RT)/(Tc2−RT)≧1.8 where Tc2: Curie temperature of the cutoff layer, and RT: room temperature.

Abstract: A magneto-optical recording medium has magneto-optical recording layers (11, 12, 13) and reproducing layers (21, 22, 23). The information recorded in the reproducing layers are reproduced by means of reproducing light beams (31, 32, 33) of different wavelengths, respectively. In reproduction, magnetic domains (4) recorded in the recording layers are transferred in the reproducing layers formed on the respective recording layers, the transferred magnetic domains (5) are enlarged with an external magnetic field, and the information is reproduced. Since information is recorded and reproduced for each recording layer, the recording density is improved. Further since the reproduction signals are amplified by the magnetic domain enlargement, the C/N is improved.

Abstract: A magneto-optical recording medium 11 is irradiated with a reproducing light beam 13 so that only a minute magnetic domain 313b, which is subjected to recording in a recording layer 18 and which is smaller than ½ of a spot radius of the recording light beam 13, is selected by a gate layer 17 and transferred to a magnetic domain-magnifying and reproducing layer 3. The magnetic domain transferred to the magnetic domain-magnifying and reproducing layer 3 is magnified by using a magnifying and reproducing magnetic field 411 of an alternating magnetic field. A large reproduction signal is obtained from the magnified magnetic domain 419, and the minute magnetic domain can be subjected to reproduction at a high resolving power and at a high S/N ratio. The magnified magnetic domain 419 is reduced by using a reducing reproducing magnetic field 415 of the alternating magnetic field. The gate layer 17 has a thickness which is not less than a thickness of a magnetic wall of the magnetic domain.

Abstract: A magneto-optic recording medium, which has a multilayered magnetic layer including a recording layer and a reproducing layer, is capable of reproducing a micro mark by utilizing a temperature distribution generated by laser beam irradiation for transferring a domain wall from the recording layer to the reproducing layer and by utilizing the movement of the domain wall. Each of the recording areas is arranged so that the recording area is adjacent to a magnetic partition area of a neighboring track. The recording areas and the magnetic partition areas are arranged alternately in one track, and an edge of a record mark is positioned in the recording area. Preferably, when reproducing information recorded on this magneto-optic recording medium, two neighboring tracks are irradiated with one laser beam for reproduction so that high speed transmission can be performed.

Abstract: A magneto-optical recording medium includes a substrate and a reproducing layer and a recording layer provided on the substrate. A recording magnetic domain is provided in the recording layer by heating the recording layer by irradiation with light and applying a recording magnetic field to the recording layer in such a manner that information is recorded in the recording layer. The recording layer is a magnetic film having magnetic anisotropy in a direction perpendicular to the film surface, and the magnetic film holds the recording magnetic domain formed therein. The magneto-optical recording medium further comprises a intermediate layer and a reproducing aid layer between the reproducing layer and the recording layer. Saturated magnetization of the reproducing aid layer increases with an increase in the temperature of the reproducing aid layer.

Abstract: By irradiating a light beam between recording tracks of the magneto-optical recording medium, the magnetic anisotropy of at least one layer selected from the group consisting of the domain wall displacement layer and the recording layer formed between the recording tracks can be made lower than that of said layers on the recording tracks, and a bias magnetic field is applied at least between recording tracks while a light beam is radiated. Because of this, initialization of a medium may be conducted simultaneously.

Abstract: A magneto-optical storage medium includes an interference layer, a magnetic domain expansion layer, an intermediate layer, a magnetic masking layer, a recording layer, and a protection layer which are sequentially formed on a substrate. The magnetic domain expansion layer produces a smaller frictional force due to wall coercivity than do the other magnetic layers. The intermediate layer has the Curie temperature TC2 which is lower than those of the other magnetic layers. The magnetic masking layer is in a perpendicular magnetization state at temperatures that are in a proximity of TC2, and changes into an in-plane magnetization state at temperatures that are higher than the proximity of TC2. The recording layer produces a higher coercive force than those produced by the magnetic domain expansion layer at room temperature.

Abstract: A phase error detection apparatus and method is disclosed whereby a data signal is played back at a high S/N ratio from a magneto-optical disk making use of a ghost signal by magnetic domain wall displacement detection while the playback laser poser is kept at an optimum level. First, the laser power is controlled so that the time delay of a ghost signal from a data signal may be equal to a fixed multiple of a data detection clock. Thereupon, a laser power control section searches for a point at which the amount of jitters generated is small based on a RF signal. Then, the playback laser power is adjusted so that the time delay amount of the ghost signal from the data signal may be the fixed multiple n=5 of the clock nearest to the phase delay amount set in advance of a ghost which appears in the isothermal region with a laser power with which an optimum signal characteristic is obtained.

Abstract: A magneto-optical recording medium 11 has, in order from the laser irradiation side, a second auxiliary magnetic film 4, first auxiliary magnetic film 5, and magneto-optical recording film 6. First and second auxiliary magnetic films 4 and 5 change from in-plane magnetization to perpendicular magnetization when their respective critical temperatures TCR1 and TCR2 are exceeded. The Curie temperatures TC0, TC1 and TC2 of the magneto-optical recording film and the first and the second auxiliary magnetic films 4, 5 and their critical temperatures TCR1 and TCR2 satisfy the relationship: room temperature<TCR2<TCR1<TC0, TC1,TC2. The first auxiliary magnetic layer has a film thickness greater than the thickness of the magnetic wall. In response to irradiation by the reproducing light beam, recording magnetic domain 22 of magneto-optical recording film 6 is transferred, with size reduction, to first auxiliary magnetic film 5 and is then transferred, with magnification, to second auxiliary magnetic film 4.

Abstract: A magneto-optical medium of a domain wall displacement type is provided which does not cause inward leakage of signals caused by domain wall displacement from the rear of a reproducing light spot. The magneto-optical medium comprises a domain wall displacement layer, a switching layer, and a memory layer. The switching layer has a boundary temperature higher than room temperature for transformation from a state of a perpendicular magnetization film to a state of an in-plane magnetization film.

Abstract: A magneto-optic recording medium in which information is reproduced while a recording magnetic domain is enlarged by displacing a domain wall based on a temperature distribution formed by a beam of light and having a maximum temperature Tr. The recording medium comprises a reproducing layer in which a domain wall is displaced, a recording layer for holding a recording magnetic domain corresponding to information, and a cutoff layer disposed between the reproducing layer and the recording layer and having a Curie temperature lower than those of the reproducing layer and recording layer.

Abstract: A multilayer film including a first magnetic layer, a second magnetic layer, and a third magnetic layer in the stated order is formed so that a Curie temperature TC2 of the second magnetic layer is set to be lower than a Curie temperature TC1 of the first magnetic layer and a Curie temperature TC3 of the third magnetic layer and that the third magnetic layer is a perpendicular magnetization film. In at least a part of a region at a temperature lower than TC2, the first magnetic layer is perpendicularly magnetized by exchange coupling with the second magnetic layer, and the magnetization of the third magnetic layer is transferred to the first magnetic layer via the second magnetic layer because of the exchange coupling. The second magnetic layer is made of a magnetic layer that remains in an in-plane magnetization state at room temperature and is perpendicularly magnetized in a temperature range from a critical temperature TCR higher than room temperature to the Curie temperature TC2 of the same.