Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Hideki Kitaura

Noboru Yamada

Rie Kojima

Kenichi Nishiuchi

Ken'ichi Nagata

Takashi Nishihara

Hideo Kusada

Katsumi Kawahara

Haruhiko Habuta

Yukako Doi

Shinya Abe

Shigeru Furumiya

Morio Tomiyama

Shigeaki Furukawa

Tetsuya Akiyama

Takeo Ohta

Yoshitaka Sakaue

Takeshi Sakaguchi

Hiroyuki Ohta

An optical information recording medium includes a recording film, which contains germanium, bismuth, and at least 50 at % tellurium, and has a first recording film component formed in the planar direction and having a bismuth content of at least 15 at %, a second recording film component formed in the planar direction on the side to be irradiated with a light beam and having a bismuth content that is at least 10 at % lower than that of the first recording film component, and an intermediate recording film component provided between the first and second recording film component to moderate the change in the bismuth content in the film thickness direction between the first and second recording film component, and having a bismuth content greater than the bismuth content of the second recording film component and less than the bismuth content of the first recording film component.

Optical information recording medium and method for manufacturing same

In an optical information recording medium of the present invention, at least one information layer provided on a transparent substrate includes a protective layer and a write-once recording layer that are disposed in this order from the transparent substrate side. The recording layer contains at least one selected from Cr&#x2014;O, Zn&#x2014;O, Ga&#x2014;O, In&#x2014;O, Sn&#x2014;O, Sb&#x2014;O, Bi&#x2014;O, and Te&#x2014;O. The protective layer contains at least one selected from Cr&#x2014;O, Zn&#x2014;O, Ga&#x2014;O, In&#x2014;O, Sn&#x2014;O, Sb&#x2014;O, Bi&#x2014;O, and Te&#x2014;O. When the total amount of all the atoms other than oxygen atoms contained in the protective layer is taken as 100 atom %, the total amount of atoms of Cr, Zn, Ga, In, Sn, Sb, Bi, and Te in the protective layer is at least 70 atom %.

Optical information recording medium, method and apparatus for recording and reproducing for the same

An optical information recording medium, recording/reproducing method thereof, and recording/reproducing apparatus with superior signal quality for high-density recording that has high storage reliability is provided. The optical information recording medium has at least one information layer having a recording layer and a dielectric layer in order on a transparent substrate. The dielectric layer is comprised of greater than or equal to 50 molecule percent and less than or equal to 98 molecule percent of Zn&#x2014;O, and greater than or equal to 2 molecule percent to less than or equal to 50 molecule percent of one or more compounds selected from the group consisting of Y&#x2014;O, Ce&#x2014;O, Nb&#x2014;O, Ta&#x2014;O, Cr&#x2014;O and Mo&#x2014;O.

Optical information recording medium, recording/reproducing method thereof and recording/reproducing apparatus

An optical information recording medium that can simultaneously achieve both a high transmittance and high signal quality of an information layer, improve the reliability of long-term conservation, and reduce the manufacturing cost, and a manufacturing method thereof are provided. In an optical information recording medium including at least one information layer on a substrate, at least one of the information layers has a recording layer and a dielectric layer, the recording layer contains Te, O, and M (M is one or a plurality of elements selected from Au, Pd, and Pt) as major components, the dielectric layer has a thermal conductivity of 0.01 W/K&#xb7;cm or more, and the dielectric layer has an extinction coefficient of 0 through 1.0 inclusive.

Optical information recording medium and method for manufacturing the same

An optical information recording medium includes one or more information layers including a recording layer for recording/reproducing an information signal by irradiation with a laser light, and a seperating layer or a protective substate on which a first information layer of the information layer on the irradiation face side is formed. The seperating layer or the protective substrate having a guide groove spirally or concentrically formed on the surface, and the respective inclined planes on the inner perimeter side and the outer perimeter side of the guide groove having inclined angles &#x3b1; and &#x3b2; with respect to the bottom face of the guide groove. The guide groove has one or more dissymmetric regions in the radius direction where the inclined angles &#x3b1; and &#x3b2; are different. The information layer has roughly agreeing thicknesses in the inclined face portion on the inner and outer perimeter sides in the dissymmetric region.

Optical information recording medium and manufacture method thereof

An optical information recording medium includes the first to the n-th information layers (where n is an integer not less than 3) arranged in this order from a laser beam incident side. Each information layer includes a recording layer containing Te, O and M, where M denotes at least one element selected from the group consisting of Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Zr, Nb, Mo, Ru, Rh, Pd, Ag, In, Sn, Sb, Hf, Ta, W, Re, Os, Ir, Pt, Au and Bi. Concentrations of oxygen atoms contained in the first to the n-th recording layers, namely C(1) to C(n&#x2212;1), satisfy the following relationships: C(1)&#x2267;C(2)&#x2267; . . . &#x2267;C(n&#x2212;2)&#x2267;C(n&#x2212;1), and C(1)&#x2260;C(n&#x2212;1). When two information layers are included, the oxygen atom concentration of the first information layer is made larger than that of the second information layer.

A recording medium has at least a recording layer on a transparent substrate. The recording layer has at least a first phase-changeable film and a second phase-changeable film in that order, starting on the side closest to the transparent substrate. The first phase-changeable film and the second phase-changeable film each contains at least 10 atom % and no more than 50 atom % germanium and at least 45 atom % and no more than 60 atom % tellurium. Also at least one of the phase-changeable films contains bismuth.

Optical information recording medium, and manufacturing method, recording method, and recording apparatus thereof

The present invention provides an optical information recording medium of excellent signal quality in high density recording onto a semitransparent information layer, its manufacturing method and a manufacturing apparatus. The optical information recording medium of the present invention includes at least a semitransparent information layer disposed between a circular transparent substrate and a protective substrate, in which the information layer has spiral grooves for guiding a light beam, and also includes a recording film capable of recording/reproducing information thereon/therefrom by changing at least in two states detectable optically by irradiation of the light beam from the transparent substrate side, and the difference in film thickness of slope portions of the inner circumferential side and outer circumferential side of the groove is within &#xb1;10% in the entire region for recording/reproducing information.

Optical information recording medium and method of manufacturing thereof, manufacturing apparatus, recording/reproducing method, and recording/reproducing apparatus

An optical information recording mediumincludes a first substrate, a second substratedisposed in parallel with the first substrate, and an information layerdisposed between the first substrateand the second substrate, and the information layerincludes a recording layerand inorganic layers (lower side interface layerand upper side interface layer) adjacent to the recording layer. The recording layeris changed between at least two different states, which are discernable optically, by irradiation with a laser beamincident from the first substrateside. The inorganic layer contains a nitride of SiGe(where 0.3&#x2266;x&#x2266;0.9) as a main component. The present invention provides an optical information recording medium capable of recording/reproducing information with satisfactory reliability even in recording/reproducing with a light beam having a short wavelength or in recording/reproducing with respect to a plurality of information layers.

Optical information recording medium and recording method using the same

An optical information recording medium of the present invention includes a transparent substrate and a multi-layered film provided on the transparent substrate. The multi-layered film includes at least a recording layer that is changed between two or more different states capable of being detected by irradiation with a light beam, and a light absorbing layer in this order from a side close to the transparent substrate. The recording layer contains a material represented by a formula: Ge(BiSb)Te(where x&#x2267;5 and 0&#x3c;y&#x2266;1) as a main component. Such a multi-layered film including a recording layer also is applicable to a multi-layered recording medium including a first information layer to an N-th information layer (N is an integer of 2 or more) disposed on a transparent substrate in this order from a side close to the transparent substrate. In this case, at least one of the first information layer to the N-th information layer has the same configuration as that of the multi-layered film.

Optical information recording medium, method for producing the medium, and method and apparatus for recording information using the medium

An optical information recording medium of the present invention includes at least one information layer. The information layer includes a first protective film, a first interface film, a recording film having the optical characteristics that are changed reversibly by laser beam irradiation, a second interface film, a second protective film, and a reflective film, present in the indicated order from the laser beam incident side. The first interface film includes an oxide of at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and Si. The second interface film includes carbon or a carbide of at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and Si.

Optical information recording medium and manufacturing method and recording/reproducing method for the same

An information recording medium ensures high reliability and favorable overwrite cycle-ability even when an interface layer is not provided between a recording layer and a dielectric layer. The recording layer and the dielectric layers are formed on the surface of the substrate. In the recording layer, a phase change is generated between a crystal phase and an amorphous phase by irradiation of light or application of electric energy. The dielectric layers are oxide-fluoride-based material layers containing one or more oxides which each are an oxide of at least one element selected from a first group including only Ti, Zr, Cr, Hf, Nb, Ta, Cr and Si and one or more fluorides which each are a fluoride of at least one element selected from a second group including only La, Ce, Pr, Nd, Gd, Dy, Ho, Er and Yb.

Information recording medium and method for producing the same

The present invention provides a write-once optical information recording medium that can achieve a high reflectance and favorable recording and reproducing characteristics such that a high C/N ratio and high sensitivity even when information is recorded/reproduced with high density. This medium includes a transparent substrate and at least one information layer formed on the substrate. The information layer includes a recording layer made of a material including Te, O and M, where M is at least one element selected from the group consisting of Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Zr, Nb, Mo, Ru, Rh, Pd, Ag, In, Sn, Sb, Hf, Ta, W, Re, Os, Ir, Pt, Au and Bi. A reflectance with respect to a light beam incident from the side of the transparent substrate after recording information on the recording layer is lower than a reflectance before recording.

Optical information recording medium, method for producing the same, and method and apparatus for recording information thereon

An optical information recording medium of the present invention includes a first substrate, a second substrate placed in parallel with the first substrate, and an information layer placed between the first substrate and the second substrate, wherein the information layer includes a recording layer and a dielectric layer (lower dielectric layer/upper dielectric layer) placed so that a distance from the dielectric layer to the recording layer is 20 nm or less. The recording layer is changed between at least two different states that can be identified optically by irradiation of a laser beam incident from the first substrate side, and the dielectric layer contains ZnS and Si as main components.

An optical information recording medium includes a first information layer, a separating layer, a second information layer and a protective substrate in this order on a transparent substrate. The second information layer comprises an optical interference layer, a lower protective layer, a recording layer, an upper protective layer, and a reflective layer in this order from the side near the transparent substrate. The reflective layer has a refractive index of at least 2.5 at a wavelength &lgr; of light beams. The second information layer is a reflectance-increase type where the reflectance with respect to the light beams incident from the transparent substrate side after recording is higher than that before recording. It is possible not to provide the optical interference layer if the ratio n /n of the refractive index n at the wavelength &lgr; of the recording layer before recording to the refractive index n thereof after recording is not more than 0.8.

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Souraku-gun, Japan

Hideki Kitaura