Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Rie Kojima

Noboru Yamada

Takashi Nishihara

Akio Tsuchino

Hideo Kusada

Hideki Kitaura

Yoshitaka Sakaue

Yukako Doi

Kenichi Nishiuchi

Kenji Narumi

Haruhiko Habuta

Masahiro Birukawa

Ken'ichi Nagata

Takeshi Sakaguchi

Tomoyasu Takaoka

Toshiyuki Matsunaga

Kazuhisa Yamamoto

Kiminori Mizuuchi

Eiji Ohno

Nobuo Akahira

Naoyasu Miyagawa

Shigeaki Furukawa

Kenichi Nagata

Katsumi Kawahara

Mayumi Uno

Toshiaki Kashihara

Keiichiro Horai

Eiichi Ito

Tosiyuki Matunaga

Kazuki Aita

Toshiyuki Matunaga

An information recording medium and a method for producing the same according to the present disclosure are configured to have an information layer in which a larger amount of light for reproduction can be obtained, so that the medium is suitable for recording information at high recording density and is useful for a multi-layer optical disc that records a large amount of contents.

Information storage medium having multiple recording layers

An information recording medium according to the present disclosure is an information recording medium of a write-once-read-many type and records or reproduces information when irradiated with laser light. The information recording medium includes: a substrate; a plurality of information layers at least one information layer of which includes a recording film that is a W&#x2014;O-based recording film comprising at least tungsten (W) and oxygen (O); and a dielectric film A in contact with the W&#x2014;O-based recording film, the dielectric film A comprising at least 30 mol % tin oxide.

Information recording medium and method for manufacturing information recording medium

An information recording medium including three or more information layers, wherein: at least one information layer includes a recording layer and a nucleation layer; the recording layer contains a material that is represented by formula (1) [(GeTe)(InTe)]Sb(mol %) with x satisfying 0.8&#x2266;x&#x3c;1.0 and y satisfying 95&#x2266;y&#x3c;100; the nucleation layer contains a material that is represented by formula (2) (GeTe)(BiTe)(mol %) with z satisfying 10&#x2266;z&#x2266;71; and the nucleation layer is in contact with the recording layer. This information recording medium is capable of achieving sufficient signal amplitude even in cases where a small recording mark is formed, and is also capable of stably maintaining a small recording mark.

Information recording medium and method for producing same

An optical information recording medium including three or more information layers, wherein at least one information layer provided on the light incident side is an information layer which enables information to be overwritten and includes a recording film, a transmittance adjusting film of a dielectric containing Bi, Ti and O, and an isolation film in this order from a light incident side; and the isolation film is provided between and adjacent to the transmittance adjusting film and an intermediate separation layer which separate the information layer from another information layer on the side opposite to the light incident side; and the isolation film has an optical constant at a wavelength of 405 nm such that a refractive index is 1.8 or less and an extinction coefficient is 0.05 or less. This information recording medium prevents the repeated overwriting characteristics in a sever environment from being deteriorated.

Information recording medium and method for manufacturing the same

An optical information recording medium of the present invention includes at least a recording layer () that allows information to be recorded thereon and/or reproduced therefrom by being irradiated with a laser beam, and a transmittance adjusting layer () in this order from an incident side of the laser beam (). In the optical information recording medium of the present invention, the transmittance adjusting layer () contains Bi, Ti, and O and with a composition of Bi, Ti, and O contained in the transmittance adjusting layer () being denoted as BiTiO, in atomic number ratio, x, y, and z satisfy 0.07&#x2266;x&#x2266;0.35, 0.07&#x2266;y&#x2266;0.28, 0.56&#x2266;z&#x2266;0.70, and x+y+z=1. Or the transmittance adjusting layer () contains BiOand TiO, and with a composition of BiOand TiOcontained in the transmittance adjusting layer () being denoted as (BiO)(TiO), in molar ratio, &#x3b1; and &#x3b2; satisfy 0.2&#x2266;&#x3b1;&#x2266;0.7, 0.3&#x2266;&#x3b2;&#x2266;0.8, and &#x3b1;+&#x3b2;=1.

Optical information recording medium and method for manufacturing the same

The information recording medium () of the present invention includes: an information layer () including a recording layer () capable of changing its phase containing at least one selected from Ge&#x2014;Te, Sb&#x2014;Te and Ge&#x2014;Sb, and two or more dielectric layers () disposed on the optical beam incident side with respect to the recording layer (); and a transparent layer () disposed on the optical beam incident side with respect to the information layer () adjacent to the information layer, made of a transparent material with respect to the optical beam, and having a refractive index n of 1.75 or more. When two dielectric layers () from the near side to the transparent layer () each are referred to as a dielectric layer b () and a dielectric layer a () from the optical beam incident side among the two or more dielectric layers (), a relationship of the refractive index n of the transparent layer, a refractive index nof the dielectric layer b () and a refractive index nof the dielectric layer a satisfies n&#x3c;n&#x3c;n. In the information recording medium () of the present invention, information can be recorded or reproduced by means of an optical system having a numerical aperture (NA)&#x3e;1 by irradiation with optical beam.

Information recording medium and recording/reproducing method for the same

An information recording medium () of the present invention is an information recording medium with respect to which information can be recorded or reproduced by irradiation with an optical beam (). The information recording medium () includes a second interface layer (), a recording layer () and a first interface layer () in this order from the optical beam () incident side. The first interface layer () and the second interface layer () are disposed in contact with the recording layer (). The second interface layer () contains M1 (where M1 is at least one element selected from Nb, Y, Dy, Ti, Si and Al), Cr and oxygen (O). The first interface layer () contains M2 (where M2 is at least one element selected from Nb, Y, Dy, Ti, Si, Al, Zr and Hf), Cr and oxygen (O). The first interface layer () and the second interface layer () each contain Cr in a range of 50 mol % or less in terms of the oxide (CrO).

Information recording medium

An optical information recording medium () of the present invention includes an information layer () that allows information to be recorded thereon and reproduced therefrom by irradiation with a laser beam (). The information layer () includes a reflective layer (), a first dielectric layer (), a recording layer () capable of undergoing a phase change by the irradiation with the laser beam () and a second dielectric layer () formed in this order from a side opposite to a laser beam incident side. The recording layer () contains Ge, Sb and Te. When Ge, Sb and Te contained in the recording layer () are represented by GeSbTein atomic number ratio, x, y, and z satisfy 0.39&#x2266;x&#x2266;0.48, 0.02&#x2266;y&#x3c;0.11, 0.40&#x2266;z&#x3c;0.56, and x+y+z=1. The recording layer () has a thickness of at least 10 nm but not more than 15 nm. In the case where a ratio of an amount of reflected light of the laser beam () from the information layer () to an amount of the laser beam () incident on the information layer () is denoted as R (%), the R when the recording layer () is in a crystalline state is denoted as Rc (%), and the R when the recording layer () is in an amorphous state is denoted as Ra (%), Rc and Ra satisfy 6.0&#x2266;Rc/Ra&#x2266;12.0 and 1.0&#x2266;Rc&#x2266;3.0.

Optical information recording medium and recording/reproducing method therefor

The information recording medium () of the present invention includes a recording film (). The information recording medium () allows information to be recorded and reproduced on and from the information recording medium by irradiation of the recording film () with a laser beam (). The information recording medium () of the present invention further includes a mixed dielectric film (the second dielectric film) disposed on the laser beam () incident side with respect to the recording film (). The mixed dielectric film contains a mixed dielectric material consisting of Zn sulfide, Si oxide and an oxide X (where the oxide X is an oxide of at least one element selected from Ti, Nb, Ta and Ce).

Information recording medium and method for producing the same

In an information recording medium that has an information layer which includes a recording layer capable of undergoing phase transition, the recording layer is formed from a material that contains Sb and S, and has composition represented by the formula (1): SbS(atomic %) where suffix x represents the proportion in atomic % that satisfies a relationship of 50&#x2266;x&#x2266;98.

Information recording medium, process for producing the information recording medium, sputtering target and film forming apparatus

An information recording medium () of the present invention is an information recording medium allowing information to be recorded thereon by irradiation with a laser beam or by application of electrical energy. The information recording medium () includes a recording layer () capable of undergoing a phase change by the irradiation with the laser beam or by the application of the electrical energy. The recording layer () contains Sb, Te, Ge, and C, and a content of Te in the recording layer () is at least 8 atom % but not more than 25 atom %.

Information recording medium and method for producing same, and sputtering target

An information recording medium () of the present invention is an information recording medium that allows information to be recorded thereon by being irradiated with an optical beam or by being applied with electrical energy, and includes at least a recording layer () whose phase can change. The recording layer () contains antimony (Sb), carbon (C), and a light element (L) having an atomic weight of less than 33. The light element (L) preferably is at least one element selected from B, N, O, Mg, Al, and S. For example, the recording layer () may be composed of a material represented by a composition SbCL, where the subscripts 100-x-y, x, and y denote composition ratios of Sb, C, and the L in atomic percentage, respectively, and x and y satisfy x+y&#x2266;50.

Information recording medium, method for producing the same, and sputtering target

An optical information recording medium () of the present invention is an optical information recording medium including: N information layers, where N is a natural number of 2 or more; and an intermediate layer for separating the N information layers optically from each other. With the N information layers being referred to as a first information layer () to an N-th information layer () sequentially from an optical beam incident side, a first information layer () corresponding to an L-th information layer included in the N information layers includes a recording layer () on which information can be recorded by irradiation with an optical beam, a reflective layer (), and a transmittance adjusting layer () in this order from the optical beam incident side, where L is an at least one natural number that satisfies 1&#x2266;L&#x2266;N&#x2212;1. The transmittance adjusting layer () contains tungsten (W) and oxygen (O).

Optical information recording medium, method of manufacturing the same, and sputtering target

An information recording medium ensuring high recording and erase function and excellent archival characteristic at a high linear velocity and over a wide range of linear velocities is provided. Such a medium is obtained by constructing a recording layer which has a composition that can generate phase change as a whole, of a first through an M-th constituent layers (wherein M is an integer of 2 or greater) which are stacked in a thickness direction, such that elemental compositions of contiguous an m-th constituent layer and a (m+1)th constituent layer are different from each other (wherein m is an integer and satisfies 1&#x2266;m&#x2266;M) assuming that the constituent layer located at an m-th position from a laser light incident side is the m-th constituent layer. In this information recording medium, at least one m-th constituent layer constituting the recording layer preferably includes at least one element selected from Te, Bi, Sb, Ge, In, Ga, Al, Sn, Pb, Se and Si.

An information recording medium is provided that has high recording sensitivity and high erasability, even when a recording layer thereof is as thin as about 3 nm. An information recording mediumon which information can be recorded by applying light or electrical energy has at least a recording layerthat undergoes phase change, while the recording layercontains at least one element selected from among Zn, Si and C, and Sb in total proportion of 85 atomic % or more and has a composition preferably represented by the formula SbM1(atomic %) (wherein M1 represents at least one element selected from among Zn, Si and C, and a1 is a proportion in terms of atomic % that satisfies a relationship of 0&#x3c;a1&#x2266;50).

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Osaka, Japan

Rie Kojima