Abstract: A method of manufacturing a grinding wheel includes a surface unevenness forming step of applying ultrasonic vibrations from an ultrasonic vibration applying unit through water to an annular slot defined in a surface of an annular base along circumferential directions thereof, thereby forming surface unevennesses on either one or both of a side surface and a bottom surface of the annular slot, and, after the surface unevenness forming step, a grindstone fixing step of fixing a plurality of grindstones to the annular slot with an adhesive.

Abstract: A grinding apparatus includes a chuck table that holds a workpiece through a protective tape, where the protective tape is attached to one surface of an annular frame so as to cover an opening of the annular frame and the workpiece is attached to the protective tape on an inner side of an inner circumferential edge of the opening of the annular frame; a grinding unit for grinding the workpiece; and a frame cleaning unit that cleans the other surface located on a side opposite to the one surface of the annular frame obtained after grinding of the workpiece, and wherein the frame cleaning unit has either: (i) a first cleaning member configured and arranged for making contact with the other surface of the annular frame and having flexibility, or (ii) a second cleaning member that jets at least either gas or liquid from above the other surface of the annular frame.

Abstract: A vitrified bond grindstone includes abrasive grains and a bonding material for fixing the abrasive grains, the bonding material includes a parent material containing SiO2 as a main constituent, a sintering assistant oxide, and ZnO, and the content of ZnO is 11 to 15 wt % in weight ratio based on the bonding material. Preferably, the content of the sintering assistant oxide is 20 to 29 wt % in weight ratio based on the bonding material.

Abstract: A required inventory calculating system includes a first section for calculating product importance level coefficients, a second section for calculating procurement risk level coefficients, a third section for calculating general coefficients by multiplying the product importance level coefficients by the procurement risk level coefficients, a fourth section for calculating required inventory periods respectively with respect to raw materials or partly finished products by multiplying the general coefficients by a predetermined longest inventory period, and, if the required inventory periods are shorter than a predetermined shortest inventory period, setting the required inventory periods as the shortest inventory period, and a fifth section for calculating required inventories respectively for the raw materials or the partly finished products by multiplying required quantities of the raw materials or the partly finished products required to supply the products to customers or wholesalers in a predetermined p

Abstract: A determining tool for use in determining the shape of the tip end of a machining tool that machines a workpiece held on a table while the machining tool moves relatively to the table includes a bottom surface adapted to be held on the table and a flat slanting surface inclined to the bottom surface and oriented across a direction in which the machining tool moves relatively to the table, the flat slanting surface being adapted to be cut through by the tip end of the machining tool.

Abstract: A dressing tool, to be used in dressing a plurality of grindstones arrayed in an annular pattern on one surface side of a grinding wheel, includes a dressing section for dressing the plurality of grindstones, a support plate that is located on a side opposite to a front surface side of the dressing section making contact with the plurality of grindstones and that supports a back surface side of the dressing section, and an RFID tag from and in which information concerning the dressing tool is read and written. One of or both the support plate and the dressing section are provided with a recess, and the RFID tag is disposed in the recess and is fixed by a non-conductive material provided in the recess.

Abstract: A grinding apparatus includes a chuck table that holds under suction a workpiece through a protective tape, where the protective tape is attached to one surface of an annular frame so as to cover an opening of the annular frame and the workpiece is attached to the protective tape on an inner side than an inner circumferential edge of the opening of the annular frame; a grinding unit that has a grindstone for grinding the workpiece held by the chuck table; and a frame cleaning unit that cleans the other surface located on a side opposite to the one surface of the annular frame obtained after grinding of the workpiece.

Abstract: A dressing tool, to be used in dressing a plurality of grindstones arrayed in an annular pattern on one surface side of a grinding wheel, includes a dressing section for dressing the plurality of grindstones, a support plate that is located on a side opposite to a front surface side of the dressing section making contact with the plurality of grindstones and that supports a back surface side of the dressing section, and an RFID tag from and in which information concerning the dressing tool is read and written. One of or both the support plate and the dressing section are provided with a recess, and the RFID tag is disposed in the recess and is fixed by a non-conductive material provided in the recess.

Abstract: A dressing tool for dressing an annular array of grinding tones disposed on a surface of a grinding wheel includes a dressing board for dressing the grinding stones and a support plate supporting a reverse side of the dressing board. The reverse side of the dressing board has a recess defined therein that has a depth terminating short of s face side of the dressing board that is opposite the reverse side thereof and corresponding to a usage-limit thickness of the dressing board.

Abstract: A grinding apparatus for grinding a wafer stored in a cassette composed of a container for storing the wafer and a lid for enclosing the container. The grinding apparatus includes a cassette table for placing the cassette thereon, a lid removing unit for removing the lid from the cassette placed on the cassette table and leaving only the container on the cassette table, a chuck table for holding the wafer under suction, a chuck table moving unit for moving the chuck table to a grinding area, a grinding unit provided in the grinding area, the grinding unit having a grinding wheel for grinding the wafer held on the chuck table, a grinding water supplying unit for supplying a grinding water to abrasive members of the grinding wheel, and a waste water collecting unit for collecting waste water generated in grinding the wafer by operating the grinding unit.

Abstract: A grinding apparatus for grinding a wafer stored in a cassette is composed of a container for storing the wafer and a lid for enclosing the container. The grinding apparatus includes a cassette table for placing the cassette thereon, a lid removing unit for removing the lid from the cassette placed on the cassette table and leaving only the container on the cassette table, a chuck table for holding the wafer under suction, a chuck table moving unit for moving the chuck table to a grinding area, a grinding unit provided in the grinding area, the grinding unit having a grinding wheel for grinding the wafer held on the chuck table, a grinding water supplying unit for supplying a grinding water to abrasive members of the grinding wheel, and a waste water collecting unit for collecting a waste water generated in grinding the wafer by operating the grinding unit.

Abstract: A grinding method for a wafer having a plurality of devices on the front side, wherein the back side of the wafer is ground by a grinding wheel to suppress the motion of heavy metal in the wafer by a gettering effect and also to maintain the die strength of each device at about 1,000 MPa or more. The grinding wheel is composed of a frame and an abrasive member fixed to the free end of the frame. The abrasive member is produced by fixing diamond abrasive grains having a grain size of less than or equal to 1 ?m with a vitrified bond. A protective member is attached to the front side of the wafer and the wafer is held on a chuck table in the condition where the protective member is in contact with the chuck table. The grinding wheel is rotated as rotating the chuck table to thereby grind the back side of the wafer by means of the abrasive member so that the average surface roughness of the back side of the wafer becomes less than or equal to 0.

Abstract: A grinding method for a wafer having a plurality of devices on the front side, wherein the back side of the wafer is ground by a grinding wheel to suppress the motion of heavy metal in the wafer by a gettering effect and also to maintain the die strength of each device at about 1,000 MPa or more. The grinding wheel is composed of a frame and an abrasive member fixed to the free end of the frame. The abrasive member is produced by fixing diamond abrasive grains having a grain size of less than or equal to 1 ?m with a vitrified bond. A protective member is attached to the front side of the wafer and the wafer is held on a chuck table in the condition where the protective member is in contact with the chuck table. The grinding wheel is rotated as rotating the chuck table to thereby grind the back side of the wafer by means of the abrasive member so that the average surface roughness of the back side of the wafer becomes less than or equal to 0.