摘要:
A method of degrading a plastic in the presence of a biosurfactant; a method of degrading a plastic by contacting the plastic with a microorganism; a process for producing a useful substance from a plastic which comprises degrading the plastic by contacting the plastic with a microorganism and further converting the components of the thus degraded plastic with the use of a microorganism; a method of degrading a plastic by contacting the plastic with a microorganism in the coexistence of a biosurfactant and/or a plastic-degrading enzyme and thus degrading the plastic under the action of the microorganism; a transformant microorganism having been recombined with at least one DNA selected from among a DNA containing a gene encoding a surface active substance, a DNA containing a gene encoding a plastic-degrading enzyme and a DNA containing a gene encoding a useful substance; novel genes as described above; and proteins encoded thereby.
摘要:
An apparatus for polishing wafers comprising a turn table with a polishing pad fixedly extended thereon, at least one polishing head positioned above a point on the turn table spaced by a distance from its center, a plate mounted on a lower surface of the at least one polishing head, and a carrier, which is used for retaining the wafers, mounted on the plate in a manner such that the carrier is freely rotatable relative to the plate, wherein a backing pad which is used to press the wafers is fixed on the plate and the wafers are rotated around their respective centers, while being revolved around the center of the plate. According to the apparatus, polished wafers with an excellent flatness are obtained in a reliable manner.
摘要:
A method and apparatus for polishing chamfers made along the periphery; of a semiconductor wafer designed such that when the wafer is once picked up by a rotatory suction cup of a transportation robot, arm, the wafer is not released from the suction cup until the entire polishing operation is completed; in an embodiment, a circular turn table having six wafer suction cups is employed which is adapted to turn step-wise, each step consisting of a turn through an angle of 60.degree. to transfer the wafers.
摘要:
An atomization roasting furnace for producing ferrite raw material powder includes an elongated roasting furnace body with a center burner located at the top end thereof. At least three liquid spray nozzles are located in an expansion slope portion below the center burner circumferentially with respect to the center burner. A quencher, located below the elongated roasting furnace body, has a top end connected to a bottom end of the elongated roasting furnace body. Quencher nozzles are located adjacent the top end of the quencher.
摘要:
A polishing apparatus of a peripheral chamfered portion of a semiconductor wafer is disclosed. The polishing apparatus comprises: a rotary drum around the periphery of which a tape having an abrasive layer thereon is wound; a first motor for rotating the rotary drum; a wafer holding mechanism which comprises a wafer holding member for holding a wafer, a second motor for rotating the wafer holding member, a supporting member for supporting the wafer holding member and the second motor, and a wafer inclining member for changing the tilt angle of the wafer with respect to the rotary drum by reciprocally rotating the supporting member on a first axis which is substantially parallel with the main surface of the wafer; and a moving member for bringing the wafer held on the supporting member into contact with or separating it from the tape wound around the rotary drum.
摘要:
An apparatus for polishing the notch of a wafer in an effective and efficient way, which comprises: a flexible tape carrying abrasive grains in the working face thereof; an infeed reel for feeding the tape stored thereon: a take-up reel for taking up the tape fed from the infeed reel; a motor for driving to rotate the take-up reel; a means for blowing a fluid to the backside surface to the edge portion of the notch to be in direct contact along the full periphery of the notch; and a means for oscillating the tape sideways.
摘要:
An apparatus for polishing the periphery portion of a wafer, by which improvement on the polishing velocity may be effected and besides a more efficient spatial usage of the working layer of an abrasive tape is capable, comprising a tape holding fixed abrasive grains thereon; a feed reel for feeding the tape stored by winding itself; a take-up reel for taking up the tape by winding itself; a rotary drum inside of which both of the reels are equipped in such a manner that they are mountable or demountable, where a portion of the tape in the way from the feed reel to the take-up reel is adaptive to wind the rotary drum around the outer cylindrical surface thereof in close contact in the shape of a helicoid and one of the main faces of the wafer is positioned to be in a plane intersecting the central axis of the rotary drum at an angle.
摘要:
A wafer chamfer polishing apparatus with a rotary circular dividing table, wherein the vacuum pump for pneumatically activating the wafer suction cups is mounted on an integral part of the rotary circular dividing table and the drive motors for dynamically activating the wafer suction cups are installed on an independent stationary body.
摘要:
A method and apparatus for polishing chamfers made along the periphery of a semiconductor wafer designed such that when the wafer is once picked up by a rotatory suction cup of a transportation robot arm, the wafer is not released from the suction cup until the entire polishing operation is completed; in an embodiment, a circular turn table having six wafer suction cups is employed which is adapted to turn step-wise, each step consisting of a turn through an angle of 60° to transfer the wafers.
摘要:
A method for chamfer mirror-like polishing a wafer having an orientation flat by rotating the wafer in a state of being pressed by a rotating buffering wheel with a predetermined pressure, is disclosed. Mirror-surface polishing a stable wafer chamfer can be obtained with a relatively simple control system. The invention is predicated in the fact that the wafer rotation speed N.sub.s has low inertial mass and low rotation speed so that the wafer rotation speed control can be obtained with high response property and high accuracy compared to pressing pressure control and buffering wheel control, and it features detecting intrinsic peripheral part, corners and orientation flat part of wafer according to a detection signal of detection means for detecting the wafer mirror-like polishing position and controlling the wafer rotation speed N.sub.s according to the detected wafer mirror-like polishing position.