Abstract: The present application discloses a doped metal oxide semiconductor which is an indium tin oxide or indium tin zinc oxide semiconductor doped with a rare earth oxide. Even at a small doping amount, the oxygen vacancies could be suppressed as well as the mobility be maintained; critically, the thin-films made thereof can avoid the influence of light on I-V characteristics and stability, which results in great improvement of the stability under illumination of metal oxide semiconductor devices. The present application also discloses the thin-film transistors made thereof the doped metal oxide semiconductor and its application.

Abstract: A thin film laminate comprises a metal layer consisting of a metal, and a thin film laminated on the surface of the metal layer, wherein a first direction is defined as one direction parallel to the surface of the metal layer, and a second direction is defined as one direction parallel to the surface of the metal layer and crossing the first direction; and the metal layer contains a plurality of first metal grains consisting of the metal and extending in the first direction on the surface of the metal layer, and a plurality of second metal grains consisting of the metal and extending in the second direction on the surface of the metal layer.

Abstract: An optical device comprising a stack of the following layers: a capping layer (16) having a high refractive index for guiding incident light; a layer of light absorber material (10), preferably a phase-changing material; and a reflective layer (12), wherein the refractive index of the capping layer is at least 1.6.

Abstract: A method is provided for detecting a fluorescent species that is reversibly photoswitchable at high frequency, and more precisely to a method for detecting at least one reversibly photoswitchable fluorescent species, including a step consisting in illuminating a sample containing a reversibly photoswitchable fluorescent species with a first illuminating light beam, of wavelength ?1, and periodically modulated at an angular frequency ?, and with a second illuminating light beam of wavelength ?2 different from ?1, which is periodically modulated at the angular frequency ?, the second illuminating light beam being modulated in antiphase with respect to the first illuminating light beam.

Abstract: Techniques for precisely controlling the composition of volatile components (such as sulfur (S), selenium (Se), and tin (Sn)) of chalcogenide semiconductors in real-time—during production of the material are provided. In one aspect, a method for forming a chalcogenide semiconductor material includes providing a S source(s) and a Se source(s); heating the S source(s) to form a S-containing vapor; heating the Se source(s) to form a Se-containing vapor; passing a carrier gas first through the S-containing vapor and then through the Se-containing vapor, wherein the S-containing vapor and the Se-containing vapor are transported via the carrier gas to a sample; and contacting the S-containing vapor and the Se-containing vapor with the sample under conditions sufficient to form the chalcogenide semiconductor material. A multi-chamber processing apparatus is also provided.

Abstract: A phase change memory device may include a phase change layer that includes a two-dimensional (2D) material. The phase change layer may include a layered structure that includes one or more layers of 2D material. The phase change layer may be provided between a first electrode and a second electrode, and the phase of at least a portion of one or more of the layers of 2D material may be changed based on an electrical signal applied to the phase change layer through the first electrode and the second electrode. The 2D material may include a chalcogenide-based material or phosphorene. The 2D material may be associated with a phase change temperature that is greater than or equal to about 200° C. and lower than or equal to about 500° C.

Abstract: Techniques for precisely controlling the composition of volatile components (such as sulfur (S), selenium (Se), and tin (Sn)) of chalcogenide semiconductors in real-time—during production of the material are provided. In one aspect, a method for forming a chalcogenide semiconductor material includes providing a S source(s) and a Se source(s); heating the S source(s) to form a S-containing vapor; heating the Se source(s) to form a Se-containing vapor; passing a carrier gas first through the S-containing vapor and then through the Se-containing vapor, wherein the S-containing vapor and the Se-containing vapor are transported via the carrier gas to a sample; and contacting the S-containing vapor and the Se-containing vapor with the sample under conditions sufficient to form the chalcogenide semiconductor material. A multi-chamber processing apparatus is also provided.

Abstract: Techniques for precisely controlling the composition of volatile components (such as sulfur (S), selenium (Se), and tin (Sn)) of chalcogenide semiconductors in real-time—during production of the material are provided. In one aspect, a method for forming a chalcogenide semiconductor material includes providing a S source(s) and a Se source(s); heating the S source(s) to form a S-containing vapor; heating the Se source(s) to form a Se-containing vapor; passing a carrier gas first through the S-containing vapor and then through the Se-containing vapor, wherein the S-containing vapor and the Se-containing vapor are transported via the carrier gas to a sample; and contacting the S-containing vapor and the Se-containing vapor with the sample under conditions sufficient to form the chalcogenide semiconductor material. A multi-chamber processing apparatus is also provided.

Abstract: A method and system for wear balancing in a flash memory device using bit error probability is disclosed. The flash memory device includes blocks with different life spans, leading potentially to one block wearing out before the other. In order to avoid this, a controller is configured to determine a bit error probability of a block and determine, based on the bit error probability, whether to select the block for storage of data. A method and system for selecting a block in a flash memory device based on the type of data is disclosed. The type of data may comprise flash management data (which may be used to manage the flash memory device) and host data. An indication of age associated with the block (such as bit error probability) is analyzed in order to determine whether to store the data in the block based on the type of data.

Abstract: Recording and erasing of data in PRAM have hitherto been performed based on a change in physical characteristics caused by primary phase-transformation of a crystalline state and an amorphous state of a chalcogen compound including Te which serves as a recording material. Since, however, a recording thin film is formed of a polycrystal but not a single crystal, a variation in resistance values occurs and a change in volume caused upon phase-transition has placed a limit on the number of times of readout of the record. In one embodiment, the above problem is solved by preparing a solid memory having a superlattice structure with a thin film containing Sb and a thin film containing Te. The solid memory can realize the number of times of repeated recording and erasing of 1015.

Abstract: A memory device includes a first electrode, a second electrode and a variable resistance layer. The second electrode includes a metal. The metal is more easily ionizable than a material of the first electrode. The variable resistance layer is disposed between the first electrode and the second electrode. The variable resistance layer includes a first layer and a second layer. The first layer has a relatively high crystallization rate. The second layer contacts the first layer. The second layer has a relatively low crystallization rate. The first layer and the second layer are stacked along a direction connecting the first electrode and the second electrode.

Abstract: Allowing the rate of phase change to be controlled at the time period of phonons (approx. 270 fs) for the purpose of achieving a substantially higher recording-erasing speed compared to what can be achieved with conventional technologies relating to optical recording media using phase change. A femtosecond pulse laser is shaped into pulse trains each having a first pulse and a second pulse using a Michelson interferometer, and the time interval of first and second pulses is matched with the time period of lattice vibration of a material constituting the phase change recording film to be irradiated, thereby inducing phase change.

Abstract: The present application discloses an information device for performing optical information processes for a recording medium including a phase-change recording layer which becomes amorphous under irradiation with pulsed amorphization light that has prescribed amorphization energy Ew. The information device includes an irradiator configured to irradiate a prescribed region of the phase-change recording layer with pulsed light and an energy setting portion which sets crystallization energy Ee for the pulsed light to crystallize the prescribed region. The crystallization energy Ee per the pulsed light, which is set by the energy setting portion, is greater than the amorphization energy Ew per the pulsed amorphization light.

Abstract: A recordable information consists of a flat polycarbonate disk having two main faces and a light sensitive film covering one main face and on which information may be recorded. The film is multi-layered with at least two elementary superposed layers, respectively containing one element A and one element B, one of the layers containing an element chosen in the Group IIIa, while the other layer contains an element chosen in Groups Va or VIa; or one of layers contains an element from Groups IIa or IIb while the other layer contains an element from Group VI. The thickness of each layer is nearly identical and the overall thickness of the light-sensitive film being at least equal to 35 nm. A burning process for safely and durably recording information on such a medium is also disclosed.

Abstract: An information recording medium (100) of the present invention includes a substrate (1) and a recording layer provided on the substrate (1) and having optical properties that can be changed by irradiation with a laser beam. The recording layer is formed of a plurality of arrayed minute recording regions (e.g., phase-change particles (2)). A part or all of the recording region is made of a recording material containing Te and O. The recording region has a length of 30 nm or less in an information recording direction. Preferably, the recording material further contains an element M, where M is at least one element selected from the group consisting of Pd, Au, and Pt.

Abstract: 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.

Abstract: An optical information recording medium 1 is constructed by sequentially layering a reflective layer 11, a protective layer 12, a recording layer 13, a protective layer 14, and a light transmissive protective layer 15 on a substrate 10. As the recording layer 13, a recording layer containing ZnS, SiO2, and Sb as principal components, or preferably, a recording layer expressed by a compositional formula [(ZnS)x(SiO2)1-x]y(SbzX1-z)1-y (where 0<x?1.0, 0.3?y?0.7, and 0.8<z?1.0 are met and X denotes at least one element selected from a group of Ga, Te, V, Si, Zn, Ta, and Tb) is adopted.

Abstract: A near-field optical disk having surface plasmon amplification by stimulated emission of radiation (SPASER) is provided. The near-field optical disk having SPASER includes a transparent substrate, a first transparent dielectric thin film layer formed on the transparent substrate, a SPASER thin film layer formed on the first transparent dielectric thin film layer, a second transparent dielectric thin film layer formed on the SPASER thin film layer, a recording thin film layer formed on the second transparent dielectric thin film layer, and a third transparent dielectric thin film layer formed on the recording thin film layer.

Abstract: An optical data storage disk includes a central substrate and on each side of the substrate a pair of metal/alloy recording layers separated by a transparent layer.

Abstract: 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) [(Ge0.5Te0.5)x(In0.4Te0.6)1-x]ySb100-y (mol %) with x satisfying 0.8?x<1.0 and y satisfying 95?y<100; the nucleation layer contains a material that is represented by formula (2) (Ge0.5Te0.5)z(Bi0.4Te0.6)100-z (mol %) with z satisfying 10?z?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.

Abstract: The invention provides a master disc comprising a stack of a substrate, a phase transition material layer, a heat absorption layer provided between the substrate and the phase transition layer, and an anisotropic heat sink layer provided between the substrate and the absorption layer. Further, a method of manufacturing a master disc is provided. A stack having an upper side and a lower side is provided, wherein the stack comprises a substrate provided at the lower side of the stack, a phase transition material layer, a heat absorption layer provided between the substrate and the phase transition layer, and an anisotropic heat sink layer provided between the substrate and the absorption layer. The upper side of the stack is exposed to a laser beam and developed.

Abstract: The optical storage medium comprises a substrate layer, a data layer arranged on the substrate layer, a first nonlinear layer with a first super-resolution structure arranged above the data layer, and a second nonlinear layer with a second super-resolution structure arranged above the first nonlinear layer, the first nonlinear layer comprising a material having an increased reflectivity when irradiated with a laser beam and the second nonlinear layer comprising a material showing a transparency when irradiated with a laser beam. The first nonlinear layer comprises in particular a semiconductor material of one of the III-V semiconductor family having a low band-gap. And the second nonlinear layer comprises in particular a phase change material, for example SbTe or AIST.

Abstract: Methods for operating an apparatus for reading from or writing to a Super-RENS optical recording medium, an apparatus for reading from Super-RENS optical recording media using such methods, and a Super-RENS optical recording medium suitable for such methods are described. The super-RENS optical recording medium has location information that is readable without super-RENS effect. The location information is provided as low-frequency information. For locating a position on the super-RENS optical recording medium, a reading light beam with a power below a power necessary for achieving a super-RENS effect is generated and the location information is retrieved from the super-RENS optical recording medium.

Abstract: A multilayer-type optical recording medium having a translucent recording/reproducing functional layer containing a first protective layer, a second protective layer, a recording layer, a third protective layer, a reflective layer and a fourth protective layer in this order relative to incident laser light. The second protective layer and the fourth protective layer are made of the same kind of material. The refractive index of the second protective layer is higher by at least 0.3 than the refractive index of the first protective layer. When the film thickness of the second protective layer is set as D2, the film thickness of the fourth protective layer is set as D4, and the reflectivity before recording when the laser light is focused on the recording layer is set as R, the derivatives d(R)/d(D2) and d(R)/d(D4) have opposite signs from each other.

Abstract: An optical information recording medium of the present invention includes at least a recording layer (4) that allows information to be recorded thereon and/or reproduced therefrom by being irradiated with a laser beam, and a transmittance adjusting layer (7) in this order from an incident side of the laser beam (30). In the optical information recording medium of the present invention, the transmittance adjusting layer (7) contains Bi, Ti, and O and with a composition of Bi, Ti, and O contained in the transmittance adjusting layer (7) being denoted as BixTiyOz, in atomic number ratio, x, y, and z satisfy 0.07?x?0.35, 0.07?y?0.28, 0.56?z?0.70, and x+y+z=1. Or the transmittance adjusting layer (7) contains Bi2O3 and TiO2, and with a composition of Bi2O3 and TiO2 contained in the transmittance adjusting layer (7) being denoted as (Bi2O3)?(TiO2)?, in molar ratio, ? and ? satisfy 0.2???0.7, 0.3???0.8, and ?+?=1.

Abstract: An optical recording medium includes a support substrate, and a semi-transmissive recording layer including a first dielectric layer, a semi-transmissive semi-reflective layer, a second dielectric layer, a phase-change recording material layer, and a third dielectric layer which are laminated in that order from the support substrate side. The semi-transmissive semi-reflective layer is composed of silver, and the first dielectric layer includes a composite oxide layer using niobium oxide.

Abstract: A low-cost information recording medium is provided by which good recording quality can be obtained even when information is recorded thereon in a high density using a blue laser. The recording medium has a recording layer which comprises Sb, O and M. A content of O atoms is 30 atom % or more but not more than 55 atom %, a content of M atoms is 5 atom % or more but not more than 35 atom %, and a content of Sb atoms is 20 atom % or more but not more than 55 atom %. The recording layer does not contain Au, Pt and Pd.

Abstract: An optical recording medium includes an inorganic recording layer, a first protective layer provided on at least one surface of the inorganic recording layer and containing indium oxide, and a second protective layer provided so as to be adjacent to the first protective layer and containing titanium oxide, zirconium oxide, or tin oxide.

Abstract: An optical recording medium includes a support substrate and a semi-transmissive recording layer. The semi-transmissive recording layer includes a first dielectric layer, a semi-transmissive semi-reflective layer, a second dielectric layer, a phase change recording material layer, and a third dielectric layer that are sequentially stacked in that order on the support substrate. The semi-transmissive semi-reflective layer contains silver. The second dielectric layer has a stack structure including a lower layer disposed at the interface on the semi-transmissive semi-reflective layer side and an upper layer disposed on the phase change recording material layer side of the lower layer. The lower layer is composed of indium oxide or a composite oxide of indium oxide and tin oxide. The upper layer is composed of tantalum oxide, gallium oxide, zirconium oxide, or niobium oxide.

Abstract: A multilayer optical recording medium including at least multiple information layers each having at least a phase change recording layer capable of recording information by laser irradiation and a reflection layer, wherein each information layer other than the innermost information layer as seen from a side of the laser irradiation has at least a lower protection layer, the phase change recording layer, an upper protection layer, the reflection layer and an optical transmission layer, the upper protection layer and the optical transmission layer in each information layer other than the innermost information layer as seen from the side of the laser irradiation are composed of an Sn oxide-containing material and a thickness of the upper protection layer in each information layer other than the innermost information layer as seen from the side of the laser irradiation is 2 nm to 15 nm is provided.

Abstract: An optical information recording medium (100) of the present invention includes an information layer (011) that allows information to be recorded thereon and reproduced therefrom by irradiation with a laser beam (040). The information layer (011) includes a reflective layer (002), a first dielectric layer (003), a recording layer (005) capable of undergoing a phase change by the irradiation with the laser beam (040) and a second dielectric layer (007) formed in this order from a side opposite to a laser beam incident side. The recording layer (005) contains Ge, Sb and Te. When Ge, Sb and Te contained in the recording layer (005) are represented by GexSbyTez in atomic number ratio, x, y, and z satisfy 0.39?x?0.48, 0.02?y<0.11, 0.40?z<0.56, and x+y+z=1. The recording layer (005) has a thickness of at least 10 nm but not more than 15 nm.

Abstract: An information recording medium (9) 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 (1). The information recording medium (9) includes a second interface layer (103), a recording layer (104) and a first interface layer (105) in this order from the optical beam (1) incident side. The first interface layer (105) and the second interface layer (103) are disposed in contact with the recording layer (104). The second interface layer (103) 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 (105) 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 (105) and the second interface layer (103) each contain Cr in a range of 50 mol % or less in terms of the oxide (Cr2O3).

Abstract: Disclosed herein is a recording material for an optical recording medium. The recording material has a composition represented by a general formula of BixGeyO(1-x-y), in which x and y respectively are atomic ratios of bismuth and germanium, and satisfy the requirements of the following formulae: 2.8?(x/y)?25 and 0.55?(1?x?y)?0.62.

Abstract: An optical recording media includes a substrate, a cap layer opposite to the substrate, at least one first stacked recording structure, at least one second stacked recording structure, and a space layer. The first stacked recording structure including a first recording layer disposed between the substrate and the cap layer and a reflective layer disposed between the substrate and the first recording layer is disposed between the substrate and the cap layer. The second stacked recording structure including a second recording layer disposed between the substrate and the cap layer and an Nb2O5 interface layer disposed between the substrate and the second recording layer is disposed between the substrate and the cap layer. The spacer layer is disposed between the first and second stacked recording structures, the first stacked recording structures, and the second stacked recording structures. One of the first stacked recording structures is disposed directly on the substrate.

Abstract: A write-once optical recording medium includes an inorganic recording layer and a protective layer provided on at least one surface of the inorganic recording layer. This protective layer contains indium oxide and tin oxide as main components.

Abstract: An optical information recording medium in which recorded information is stably stored for long time in the initial state, signals are not deteriorated by a laser beam for reproduction at the time of signal reproduction, the quality does not change in normal long-term storage, the write characteristic is held, a manufacturing cost is reduced, a margin in the manufacture process is assured, and excellent recording/reproducing characteristics are obtained in the wide range of linear speeds and recording powers is provided. An optical information recording medium 1 is formed by sequentially stacking a first information recording layer 11, an intermediate layer 12, a second information recording layer 13, and a protection layer 14 on a substrate 10. As a material of a recording layer 13b of the second information recording layer 13, a material having a composition expressed by [(ZnS)x(SiO2)1-x]y(SbzX1-z)1-y (where 0<x?1.0, 0.3?y?0.7, 0.8?z?1.

Abstract: An optical information recording medium includes: a supporting substrate; a light-transmitting protective layer which becomes a layer on the incident side of recording and reproducing laser light; and an information recording layer intervening between the supporting substrate and the light-transmitting protective layer, wherein the information recording layer includes a phase-change material layer, a dielectric layer and a metal layer in this order from the incident side of laser light; and the dielectric layer is constituted of, as a main component, (In2O3)x(SnO2)1-x, wherein x is satisfied with the relationship of (0.4<x?0.7).

Abstract: An optical recording medium includes: a substrate; an information recording layer that is formed on the substrate and that has a recording film, which contains Zn or Al, Pd, and oxygen and in which the amount of oxygen is larger than that in a stoichiometric composition when Zn or Al is completely oxidized to become ZnO or Al2O3; and a light transmissive layer formed on the information recording layer.

Abstract: An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam.

Abstract: An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam.

Abstract: An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam.

Abstract: An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam.

Abstract: An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam.

Abstract: An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam.

Abstract: An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam.

Abstract: An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam.

Abstract: An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam.

Abstract: An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam.

Abstract: An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam.

Abstract: An information recording medium comprising a substrate having a recording surface provided with emboss pits or guiding grooves, a reflective film formed on the recording surface of the substrate, and a first protective film formed on the reflective film. This information recording medium is featured in that both sides of the information recording medium are constituted by a first surface provided with the protective film and by a second surface formed opposite to the first surface, and that an irradiated light beam is irradiated through the first surface, a recorded information being reproduced based on changes in light intensity of the reflected light beam.