摘要:
The present invention are a method for producing a silicon wafer having a crystal orientation from a silicon single crystal ingot grown by a Floating Zone method (FZ method), wherein, at least, an FZ silicon single crystal ingot is grown by being made to be dislocation-free by Dash Necking method using a seed crystal having its crystal axis inclined at a specified angle from a crystal orientation , and the grown FZ silicon single crystal ingot is sliced at the just angle of a crystal orientation to produce a silicon wafer having a crystal orientation , and a silicon wafer produced by the method. Thereby, there are provided a method for producing a silicon wafer having a crystal orientation from a silicon single crystal ingot made to be dislocation-free at a high success rate by using Dash Necking method by FZ method, and a silicon wafer having an crystal orientation .
摘要:
A magnetic recording medium comprises a nonmagnetic support having provided thereon a plurality of magnetic layers containing a first magnetic layer as a top layer and a second magnetic layer adjacent to the first magnetic layer. The first magnetic layer contains acicular magnetic powder and has a thickness of not more than 1.0 .mu.m; and the second magnetic layer contains sexangular plate-like magnetic powder.
摘要:
An optical recording disc comprises a first bonding recess formed near an outside surface of an optical recording disc in a bonding boundary portion between a cylindrical hub and a transparent disc substrate, a disc member bonded with said transparent disc substrate through said cylindrical hub, and a second bonding recess formed near the outside surface of said optical recording disc in a bonding boundary portion between said cylindrical hub and said disc member. Accordingly, said optical recording disc can prevent remainder of a bonding material for bonding a pair of said transparent disc substrates or said transparent disc substrate and said disc member together from pushing out of the outside surface of the optical recording disc, resulting in that focusing for reading and writing an information signal can be properly performed.
摘要:
A magnetic recording medium comprises a nonmagnetic support having provided thereon a plurality of magnetic layers containing a first magnetic layer as a top layer and a second magnetic layer adjacent to the first magnetic layer. The first magnetic layer contains acicular magnetic powder and has a thickness of not more than 1.0 .mu.m; and the second magnetic layer contains sexangular plate-like magnetic powder.
摘要:
The present invention are a method for producing a silicon wafer having a crystal orientation from a silicon single crystal ingot grown by a Floating Zone method (FZ method), wherein, at least, an FZ silicon single crystal ingot is grown by being made to be dislocation-free by Dash Necking method using a seed crystal having its crystal axis inclined at a specified angle from a crystal orientation , and the grown FZ silicon single crystal ingot is sliced at the just angle of a crystal orientation to produce a silicon wafer having a crystal orientation , and a silicon wafer produced by the method. Thereby, there are provided a method for producing a silicon wafer having a crystal orientation from a silicon single crystal ingot made to be dislocation-free at a high success rate by using Dash Necking method by FZ method, and a silicon wafer having an crystal orientation .
摘要:
A high-frequency induction heater for use in the growth of a semiconductor single crystal by the FZ method, including a plurality of high-frequency induction heating coils disposed in concentric juxtaposed relation to each other and each having a pair of power supply terminals provided for supplying a high-frequency current to the associated heating coil, with the power supply terminals of one of the heating coils being disposed in a space defined between opposite ends of an adjacent heating coil disposed outside the one heating coil, wherein a pair of electrically conductive members is attached to the pair of power supply terminals, respectively, of at least an innermost one of the heating coils so as to cover a space defined between the power supply terminals of the innermost heating coil. With the induction heater thus constructed, the so-called "pulsation", i.e., microscopic resistivity fluctuations and the macroscopic resistivity distribution in the diametrical and growth directions can be improved at one time.
摘要:
An optical recording disc which includes a pair of recording disc substrates opposed to each other with a space there between with a hub situated at the central portion of the disc substrates so that there is formed the closed space between the disc substrates, thereby providing a dual sided recordable optical recording disc. The hub may be formed by a pair of hub halves. There is disposed an annular inner spacer and annular outer space around the hub so as to separate the pair of recording disc substrates.
摘要:
An optical recording disc which includes a pair of recording disc substrates opposed to each other with a space therebetween, with a hub situated at the central portion of the disc substrates so that there is formed the closed space between the disc substrates, thereby providing a dual sided recordable optical recording disc. The hub may be formed by a pair of hub halves. There is disposed an annular inner spacer and annular outer spacer around the hub so as to separate the pair of recording disc substrates.