Abstract: A bioassay substrate (1) takes a flat-plate shape in which the principal surface similar to that of optical disc such as CD, etc. is circular. At the center of the substrate (1), there is formed a center hole (2) into which a chucking mechanism for rotation and holding is inserted. The substrate (1) is rotationally driven with the center hole (2) being as center. On the substrate (1), there are formed two regions of a recording region (3) and a reaction region (4) which are formed in concentrical form in a radial direction. The recording region (3) is a region where, similarly to the optical disk information recording medium, laser beams are irradiated so that recording/reproduction of information is optically performed. The reaction region (4) is a region serving as the filed of mutual reaction between probe DNA (nucleotide chain for detection) and sample DNA (marked or labeld nucleotide chain), in concrete terms, the field of hybridization reaction.

Abstract: A method for making a thin-film semiconductor device includes an annealing step of irradiating an amorphous semiconductor thin film with a laser beam so as to crystallize the amorphous semiconductor thin film. In the annealing step, the semiconductor thin film is continuously irradiated with the laser beam while shifting the position of the semiconductor thin film irradiated with the laser beam at a predetermined velocity so that excess hydrogen can be removed from the region irradiated with the laser beam without evaporating and expanding hydrogen ions in the semiconductor thin film.

Abstract: A liquid drop discharger includes a coil for generating a magnetic field based on an electric current that is applied; a moving section, removably disposed with respect to the coil so as to be movable in a central axial direction of the coil, for generating an induced current by the magnetic field generated by the coil; device for vertically applying a magnetic field to a peripheral surface of a peripheral member, where the induced current is generated, of the moving section; and a discharge opening, which moves together with the moving section, for discharging a liquid by changing the volume of a liquid chamber containing the liquid as a result of the movement of the moving section.

Abstract: Disclosed is a method of mounting chips, including the steps of: dipping a mounting board in a solvent in which chips are dispersed; and mounting the chips on the mounting board by forming electric field gradients on the mounting board in correspondence with positions where the chips are to be mounted. With this configuration, fine chips such as fine semiconductor chips can be mounted at desired positions on a mounting board with a high efficiency and a high yield.

Abstract: A liquid drop discharger includes a coil for generating a magnetic field based on an electric current that is applied; a moving section, removably disposed with respect to the coil so as to be movable in a central axial direction of the coil, for generating an induced current by the magnetic field generated by the coil; device for vertically applying a magnetic field to a peripheral surface of a peripheral member, where the induced current is generated, of the moving section; and a discharge opening, which moves together with the moving section, for discharging a liquid by changing the volume of a liquid chamber containing the liquid as a result of the movement of the moving section.

Abstract: Disclosed is a method of mounting chips, including the steps of: dipping a mounting board in a solvent in which chips are dispersed; and mounting the chips on the mounting board by forming electric field gradients on the mounting board in correspondence with positions where the chips are to be mounted. With this configuration, fine chips such as fine semiconductor chips can be mounted at desired positions on a mounting board with a high efficiency and a high yield.

Abstract: Disclosed is a method of mounting chips, including the steps of: dipping a mounting board in a solvent in which chips are dispersed; and mounting the chips on the mounting board by forming electric field gradients on the mounting board in correspondence with positions where the chips are to be mounted. With this configuration, fine chips such as fine semiconductor chips can be mounted at desired positions on a mounting board with a high efficiency and a high yield.

Abstract: Disclosed is a method of mounting chips, including the steps of: dipping a mounting board in a solvent in which chips are dispersed; and mounting the chips on the mounting board by forming electric field gradients on the mounting board in correspondence with positions where the chips are to be mounted. With this configuration, fine chips such as fine semiconductor chips can be mounted at desired positions on a mounting board with a high efficiency and a high yield.

Abstract: An apparatus for recording and/or reproducing a magneto-optical recording medium having a recording layer, a reproducing layer and an intermediate layer for magnetically coupling the recording layer and the reproducing layer in a stationary state, in which the magnetic coupling between the recording layer and the reproducing layer is only able to take place in an area in which a temperature is increased to be higher than a predetermined temperature by the radiation of a light upon reproducing and in which a recorded information held in the recording layer is read out from the reproducing layer in the radiated area. This magneto-optical recording medium is characterized in that a Curie temperature of the intermediate layer is selected to be 150.degree. C. or more. Also, an apparatus which performs the above-mentioned functions and additionally which is capable of recording and/or reproducing conventional magneto-optical discs which reproduce and/or record over the entire area of irradiation.

Abstract: A magneto-optical recording medium has a multi-layer magnetic film comprising at least a reproducing layer, a memory layer, and a recording layer which are successively deposited in magnetically coupled relationship to each other. Information is recorded on the magneto-optical recording medium selectively in a first state in which the reproducing layer and the memory layer are magnetized by copying a magnetized condition of the recording layer, with a intensity-modulated light beam of a low intensity applied to the magneto-optical recording medium, or a second state in which the reproducing layer, the memory layer, and the recording layer are magnetized by an external recording magnetic field, with a intensity-modulated light beam of a high intensity applied to the magneto-optical recording medium.

Abstract: A magneto-optic recording and reproducing medium is formed of a reproduction layer composed mainly of GdFeCo and having a saturation magnetization of at least 450 emu/cc and a coercive force of not more than 4 kOe, and a recording layer composed mainly of TbFeCo, having a coercive force of at least 5 kOe, and having a magnetization of not more than 300 emu/cc when it is a transition metal-predominant film and not more than 200 emu/cc when it is a rare earth-predominant film.

Abstract: A magneto-optical recording medium has a multi-layer magnetic film structure comprising a reproducing layer, an intermediate layer, and a record holding layer. These layers are magnetically coupled to one another. The recording medium is irradiated with a laser beam and appropriate magnetic fields are provided such that in a area of a spot of the laser beam on the recording medium, first, second and third regions are formed as a result of the temperature distribution within the laser beam spot. The first and third regions act as masking regions, with the second region between the first and third regions being a region from which magnetic signals stored in the record hold layer are transferred to the reproducing layer and are read out from the reproducing layer.

Abstract: A method of fabricating a magnetooptic recording medium (10) having at least a reproducing layer (11) and a recording layer (13), from which information is read out by changing the state of magnetization of the reproducing layer (11) comprises steps of forming the reproducing layer (11) on a substrate (21), putting a high-density magnetic recording medium (30) storing information in a high-density magnetic pattern into close contact with the reproducing layer (11) to copy the high-density magnetic pattern formed on the high-density magnetic recording medium (30) into the reproducing layer (11), and forming the recording layer (13) over the reproducing layer (11) after copying the high-density magnetic pattern into the reproducing layer, to copy the high-density magnetic pattern into the recording layer (13).

Abstract: A method and apparatus for recording and reproducing information onto and from a magneto-optic recording medium is disclosed. The magneto-optic recording medium has at least a reproducing layer and a recording layer. A recording optical head records information on the magneto-optic recording medium. A reproducing optical head has a reading light beam for reading information recorded in a region within a spot of the reading light beam by magneto-optic effect by changing a state of magnetization of the reproducing layer and at the same time irradiating the recording medium with the light beam. A wavelength of the recording light beam emitted by the recording optical head is substantially smaller than a wavelength of the reading light beam emitted by the reading optical head. A minimum ratio of the wavelength of the recording light beam to that of the reproducing light beam is 1:3.

Abstract: A demagnetizer for a magnetic head for a recording/reproducing device. The demagnetizer includes an electromagnet for producing an alternating magnetic field which gradually decreases in intensity. The demagnetizer is mounted in a case formed in the shape of a tape cassette. The electromagnet is resiliently held within the case adjacent to the opening for the magnetic head to be demagnetized. The electromagnet is energized by an oscillating drive circuit, the output of which is controlled by a capacitor.