151results about How to "Small roughness" patented technology

A method of manufacturing a large double-sided curved Fresnel lens. The method includes a machining step (A) of performing ultra-precise three-dimensional machining on an upper mold and a lower mold to each have an upper transfer surface and a lower transfer surface engaging an upper surface and a lower surface of a thermoplastic resin plate, respectively. Further, the method includes a hot press molding step (B) of pressing the thermoplastic resin plate between the upper and lower molds by a predetermined pressure with the resin plate being held at a temperature higher than a softening temperature thereof and lower than a melting temperature thereof so that the thermoplastic resin plate is curved, and both lens surfaces for the double-sided Fresnel lens are respectively transferred to an upper surface and a lower surface of the thermoplastic resin plate.

The present invention provides a magnetic disk storage system including a spindle motor that rotates a magnetic disk, a spindle motor drive circuit that rotatably drives the spindle motor, a magnetic head that performs reading of information on the magnetic disk, a voice coil motor that moves the magnetic head, and a voice coil motor drive circuit that drives the voice coil motor. When the magnetic head is loaded from a standby position to the surface of the magnetic disk, the rotational speed of the spindle motor is made slower than a rotational speed at a normal operation. Upon power-off, the spindle motor drive circuit is caused to carry out a stepup converter operation to thereby generate a voltage higher than a back electromotive voltage, and causes a control circuit and a drive circuit to operate by the high voltage to thereby enable speed control at the movement of the magnetic head to a predetermined standby position.

The invention relates to a spark plug for a gas-fired internal combustion engine, and Includes a metallic body, with an insulator fastened in the body. A central electrode, leads through the insulator and includes a protruding end of a precious metal alloy. An annular ground electrode is fastened to the body and surrounds the end of the central electrode which, at the inside thereof facing the central electrode is provided with a precious metal or with a precious metal alloy. The mutually facing surfaces of the central electrode and ground electrode formed by the precious metal or the precious metal alloy are coaxially disposed cylinder surfaces. A cap is provided and attached to the body and which, after installation of the spark plug into a combustion chamber of the internal combustion engine, shields the central electrode and the ground electrode from the combustion chamber. Together with the body of the spark plug, the central electrode forms an ante-chamber, in which the central electrode and the ground electrode are disposed. The cap having at least one opening, which enables a gas exchange between the ante-chamber and the space outside of the ante-chamber. According to the invention, a deviation of the cylinder surfaces from the ideal cylinder geometry is less than +−20 μm, and a deviation of the positions of the axes of the cylinder surfaces from their ideal coaxial position is less than +−50 μm.

The method for fabricating a semiconductor device according to the present invention comprises the step of forming a Ni film 66 on source / drain diffused layers 64, the step of performing a first thermal processing to react a lower part of the Ni film 66 and an upper part of the source / drain diffused layers 64 with each other to form Ni2Si films 70b on the source / drain diffused layers 64, the step of etching off selectively a part of the Ni film 66, which has not reacted, and the step of performing a second thermal processing to further react the Ni2Si film 70b and an upper part of the source / drain diffused layers 64 with each other.

A cyclic compound having a molecular weight of 500 to 5000 is represented by the following formula (1),wherein at least one of R0 is a monovalent group containing an iodine atom. Also disclosed are a method for producing the cyclic compound, a composition containing the cyclic compound, and a method for forming a resist pattern using the composition.

An electrospray thruster and methods of manufacturing such thrusters are provided. The micro-electrospray thruster increases the thrust density of conventional electrospray thrusters by miniaturizing the individual components of the thruster thereby allowing for the increase in the number and density of the charged particle emitters.

In order to adjust thickness of a bonded silicon single crystal film 15 depending of thickness of an SOI layer 5 to be obtained, depth of formation d1+tx of a separatory ion implanted layer 4, measured from a first main surface J, in the separatory ion implanted layer formation step is adjusted through energy of the ion implantation. Dose of the ion implantation is set smaller as the depth of formation measured from the first main surface J becomes smaller. A smaller dose results in a smaller surface roughness of the separation surface, and makes it possible to reduce polishing stock removal of the separation surface of the bonded silicon single crystal film in the planarization step. Uniformity in the thickness of the SOI layer can consequently be improved even for the case where a thin SOI layer has to be formed. The present invention is therefore successful in providing a method of fabricating an SOI wafer capable of suppressing variations in the intra-wafer and inter-wafer uniformity of the thickness of the SOI layer to a sufficiently low level, even for the case where a required level of the thickness of the SOI layer is extremely small.