Shin-etsu Handotai Co., Ltd.

Fujikoshi Machinery Corp.

Koji Kitagawa

Izumi Fusegawa

Hisashi Masumura

Hideo Kudo

Ryoji Hoshi

Tomohiko Ohta

Hiromi Kishida

Kouji Morita

Satoru Arakawa

Shiro Toyoda

Tadahiro Kato

Masahiro Sakurada

Susumu Sonokawa

Hiroshi Oishi

Junichi Ueno

Syuichi Kobayashi

Tadakazu Miyashita

Kazuya Tomii

Atsushi Kajikura

Yoshinobu Nishimoto

Yuichi Shimizu

Yukio Itoi

Tomiichi Sudou

A method for slicing a workpiece with a wire saw which includes a wire row formed by winding a fixed abrasive grain wire having abrasive grains secured to a surface thereof around multiple grooved rollers, the method including feeding a workpiece to the wire row for slicing while allowing the fixed abrasive grain wire to reciprocatively travel in an axial direction thereof, thereby slicing the workpiece at multiple positions aligned in an axial direction of the workpiece simultaneously. The method includes: supplying a coolant for workpiece slicing onto the wire row when the workpiece is sliced with the fixed abrasive grain wire; and supplying a coolant for workpiece drawing, which differs from and has a higher viscosity than the coolant for workpiece slicing, onto the wire row when the workpiece is drawn out from the wire row after the slicing of the workpiece.

Method for slicing workpiece and wire saw

A wire saw apparatus including: a wire row formed of a wire wound around a plurality of wire guides and reciprocatively travels in an axial direction; a nozzle from a coolant or slurry is supplied to the wire; and a workpiece feed mechanism presses a held workpiece against the wire row, the wire saw apparatus slice the workpiece into a wafer shape by pressing the workpiece held by the workpiece feed mechanism against the wire row and feeding it for slicing while supplying the coolant or the slurry from the nozzle to the wire, the wire saw apparatus nozzle is arranged above the wire row to be orthogonal to the wire row, and windbreak plates are arranged on both left and right sides of the arranged nozzle seen from an axial direction.

Wire saw apparatus

A method for slicing a workpiece using a wire saw which includes wire row formed by winding a fixed abrasive grain wire having abrasive grains secured to a surface around a plurality of grooved rollers, the method including feeding a columnar workpiece to wire row for slicing while allowing fixed abrasive grain wire to reciprocate and travel in an axial direction, thereby slicing the workpiece at a plurality of positions aligned in axial direction at same time. After end of slicing the workpiece, the fixed abrasive grain wire is rewound from position at the end of slicing the workpiece by length of &#x2153; or more and &#x2154; or less of the fixed abrasive grain wire fed's length from start of slicing when the workpiece and wire row begin to contact with each other to the end of slicing the workpiece, and then the workpiece is drawn out of wire row.

The present invention is directed to a method for producing a slurry used in a wire saw, including: re-pulverizing with a jet mill part or all of the abrasive grains pulverized with a roller mill or a ball mill such that the abrasive grains have an average circularity of 0.900 or more; and blending the abrasive grains whose the average circularity is 0.900 or more with a coolant to produce the slurry, and to a slurry including blended abrasive grains having an average circularity of 0.900 or more. The invention enables suppression of reduction in slicing capability due to reduction in abrasive-grains concentration and of increased costs due to reduction in slicing quality and in productivity, even when abrasive grains having a grain diameter smaller than that of #2000-size abrasive grains are used to reduce a kerf loss.

Slurry and method for producing slurry

The present invention provides a method of resuming operation of a wire saw in which slicing of a workpiece is suspended and then resumed, including slicing the workpiece while detecting a traveling direction and a traveling speed of the reciprocating wire and recording them chronologically; and resuming the slicing while controlling the traveling direction and a traveling time in the traveling direction of the wire on a basis of a wire traveling history recorded until the suspending of the slicing of the workpiece such that the reciprocating cycle of the wire becomes continuous between before the suspending and after the resuming of the slicing of the workpiece. This method enables the slicing to be completed while the nanotopography of the sliced wafer is surely prevented from degrading, even when the slicing of the workpiece with a wire saw is suspended due to, for example, breaking of the wire.

Method for resuming operation of wire saw and wire saw

The invention is directed to a method for slicing an ingot in the form of a wafer by winding a wire around a plurality of grooved rollers and pressing the wire against the ingot while making the wire travel and supplying slicing slurry to the grooved rollers, in which when the ingot is sliced, an amount of displacement of the ingot changing in an axial direction is measured and an amount of axial displacement of the grooved rollers is controlled so as to correspond to the measured amount of axial displacement of the ingot, and thereby, the ingot is sliced while controlling a relative position of the wire relative to an entire length of the ingot changing in the axial direction. As a result, a slicing method and a wire saw apparatus are provided that can perform slicing in such a way that a Bow or a Warp in a wafer obtained by slicing can be reduced, for example, by controlling a slicing path built into an ingot so that, in particular, the slicing path becomes flattened.

Slicing method and wire saw apparatus

Provided is a polishing apparatus comprising a lower stool (), a motor () and a speed reducer () for driving the lower stool, and a box () for covering at least the portion of the lower stool below the working action face. The polishing apparatus polishes a wafer by forcing the wafer to contact the lower stool and by rotating the lower stool. The box has its inside separated by partitions (and) into a plurality of regions, and the motor for driving the lower stool is arranged in a region other than the region containing the lower stool. The polishing apparatus can manufacture a wafer of a stable shape, irrespective of the time elapsed from the running start and the presence/absence of the stop of the polishing apparatus.

Polishing apparatus

A wire saw apparatus having: a wire wound around grooved rollers and axially travels in a reciprocating direction; a nozzle for supplying a slurry; and a work-feeding mechanism feeding a work toward the wire, and slicing into wafers by pressing and feeding the work against the wire traveling in a reciprocating direction while a slurry is supplied to the wire through the nozzle. A work-holding portion holds the work through a pad plate adhered to the work and a work plate, plate-shaped or block-shaped slurry-splash-blocking members are arranged in the direction of a right angle to a row of the wire wound around the grooved rollers below the work-holding portion and on both the wire cut-in side and a wire cut-out side.

A polishing head having a disklike carrier in which an annular projecting portion and a carrier-engagement portion are formed in a peripheral portion, a disklike head body in which a head-body-engagement portion is formed outside, a diaphragm for connecting the head body with the carrier, a spacer located between the carrier-engagement portion and the head-body-engagement portion in a part of the carrier-engagement portion and/or the head-body-engagement portion, in which the spacer abuts on the carrier-engagement portion and/or the head-body-engagement portion at the time of lifting the head body so that the workpiece is demounted from the polishing pad by lifting the carrier with it inclined. As a result, there is provided a polishing head in which the workpiece can be easily, safely and surely demounted from the polishing pad by lifting the polishing head holding the workpiece without overhanging the polishing head from the turn table and the like.

Polishing head, polishing apparatus and method for demounting workpiece

The present invention is a slicing method and a wire saw apparatus including winding a wire around a plurality of grooved rollers and pressing the wire against an ingot to be sliced into wafers while supplying a slurry for slicing to the grooved rollers and causing the wire to travel in a reciprocating direction, in which the ingot is sliced with controlling a temperature of the ingot by supplying a slurry for adjusting an ingot temperature to the ingot independently from the slurry for slicing while the slurry for adjusting an ingot temperature is supplied to the ingot only at the exit side of the wire caused to travel in the reciprocating direction. As a result, there is provided a method and a wire saw apparatus in which rapid cooling of an ingot especially in a time close to end of slicing of the ingot can be alleviated, consequently degradation of a nano-topography can be suppressed, and further high-quality wafers having a uniform thickness can be sliced when slicing the ingot by using a wire saw.

Slicing method and a wire saw apparatus

The present invention is a method for slicing a workpiece into wafers by pressing a cylindrical workpiece held with a workpiece holder against a wire row formed by a wire spirally wound between a plurality of wire guides and making the wire travel while supplying a slurry to a contact portion between the workpiece and the wire, wherein the workpiece is sliced with an axis direction of the workpiece inclined with respect to a plane formed by the wire row, after the workpiece is inclined in such a manner that a side far from the wire row plane is a side where the wire guides are to be axially expanded. As a result, there is provided a method for slicing that enable wafers having a good Warp shape to be obtained by precisely slicing a workpiece with a wire saw.

Method for slicing workpiece

The present invention is a polishing head provided with an annular rigid ring, a rubber film bonded to the rigid ring with a uniform tension, a mid plate joined to the rigid ring and forming a space portion together with the rubber film and the rigid ring, and an annular template provided concentrically with the rigid ring in a peripheral portion on a lower face part of the rubber film and having an outer diameter larger than an inner diameter of the rigid ring, in which a pressure of the space portion can be changed by a pressure adjustment mechanism, a back face of a work is held on the lower face part of the rubber film, and a surface of the work is brought into sliding contact with the polishing pad attached onto a turn table for performing polishing, and an inner diameter of the template is smaller than an inner diameter of the rigid ring, and a ratio between an inner diameter difference between the rigid ring and the template and a difference between the inner diameter and an outer diameter of the template is 26% or more and 45% or less. Thereby, a polishing head and the like that can obtain constant flatness stably can be provided.

Polishing head and polishing apparatus

The present invention is a wire saw in which a wire for slicing is wound around a plurality of rollers to form a wire row; the wire for slicing is driven axially in a reciprocating direction; a workpiece is sliced simultaneously at a plurality of points arranged in an axial direction by feeding the workpiece against the wire row with the workpiece cut into while a slurry is supplied to the wire for slicing; the wire saw controlling in such a manner that the workpiece is extracted while the wire is caused to travel at a speed of 2 m/min or less at the time of extracting the workpiece from the wire row after slicing the workpiece. As a result, there is provided a wire saw in which the workpiece sliced with the wire row of the wire saw can be extracted from the wire row with a simple structure without a negative influence on its slicing surface.

Method for slicing workpiece by using wire saw and wire saw

The present invention is a wire saw in which a wire is wound around a plurality of grooved rollers, the workpiece is sliced into wafers by causing the wire to travel and pressing the workpiece against the wire while a slurry is supplied to the grooved rollers, the wire saw controlling in such a manner that the workpiece is sliced while a supply temperature of the slurry is increased from the start to the end of slicing the workpiece. As a result, there is provided a wire saw in which Warp of the workpiece to be sliced can be improved by suppressing a decrease in a temperature of the workpiece in the vicinity of the slicing end portion of the workpiece and by making an increase in displacement of the grooved roller during slicing straight, that is, by making the slicing trajectory depicted in the workpiece close to a straight line.

According to the present invention, there is disclosed a silicon single crystal wafer grown according to the CZ method which is a wafer having a diameter of 200 mm or more produced from a single crystal grown at a growth rate of 0.5 mm/min or more without doping except for a dopant for controlling resistance, wherein neither an octahedral void defect due to vacancies nor a dislocation cluster due to interstitial silicons exists as a grown-in defect, and a method for producing it. There can be provided a high quality silicon single crystal wafer having a large diameter wherein a silicon single crystal in which both of octahedral void defects and dislocation clusters which are growth defects are substantially eliminated is grown at higher rate compared with the conventional method by the usual CZ method, and furthermore by controlling a concentrations of interstitial oxygen in the crystal to be low, a precipitation amount is lowered and ununiformity of BMD in a plane of the wafer is improved, and provided a method for producing it.

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Nishishirakawa, Japan

Koji Kitagawa