Provided is a method of chamfer machining a silicon wafer which makes it possible to increase the number of machining operations that can be performed using a chamfering wheel used for helical chamfer machining in the case of obtaining a small finished wafer taper angle. The method in which helical chamfer machining is performed so that the finished wafer taper angle of an edge portion in the one silicon wafer is within an allowable angle range of a target wafer taper angle .sub.0 includes a first truing step; a first chamfer machining step; a step of determining a groove bottom diameter .sub.A of the fine grinding grindstone portion; a second truing step using a second truer taper angle .sub.2; and a second chamfer machining step. The second truer taper angle .sub.2 is made larger than the first truer taper angle .sub.1.

Provided is a method of chamfer machining a silicon wafer which makes it possible to increase the number of machining operations that can be performed using a chamfering wheel used for helical chamfer machining in the case of obtaining a small finished wafer taper angle. The method in which helical chamfer machining is performed so that the finished wafer taper angle of an edge portion in the one silicon wafer is within an allowable angle range of a target wafer taper angle .sub.0 includes a first truing step; a first chamfer machining step; a step of determining a groove bottom diameter .sub.A of the fine grinding grindstone portion; a second truing step using a second truer taper angle .sub.2; and a second chamfer machining step. The second truer taper angle .sub.2 is made larger than the first truer taper angle .sub.1.

The method of the present invention comprises the steps of: previously obtaining correlation data between surface properties of the polishing pad dressed under a plurality of stages of dressing conditions and polishing effects of the work polished by the polishing pad dressed under the dressing conditions; determining an assumed dressing condition capable of achieving an object polishing effect from the correlation data; dressing the polishing pad under the assumed dressing condition determined; polishing the work; cleaning the polishing pad which has been used for polishing the work; and measuring a surface property of the cleaned polishing pad.

The method of the present invention comprises the steps of: previously obtaining correlation data between surface properties of the polishing pad dressed under a plurality of stages of dressing conditions and polishing effects of the work polished by the polishing pad dressed under the dressing conditions; determining an assumed dressing condition capable of achieving an object polishing effect from the correlation data; dressing the polishing pad under the assumed dressing condition determined; polishing the work; cleaning the polishing pad which has been used for polishing the work; and measuring a surface property of the cleaned polishing pad.

A rotary tool (21) working surface (23) includes a plurality of cutting bodies (24). The rotary tool (21) can be driven about a rotational axis (R). The actual enveloping surface (HF) of the working surface (23) is ascertained by an optical measuring arrangement (29). At least one other target variable (GS) is detected, which describes a microscopic parameter of the working surface (23). The actual variable (GI) corresponding to each specified target variable (GS) is detected by the measuring arrangement (29), and the deviation between the target variable (GS) and the actual variable (GI) is determined. If the actual enveloping surface (HF) lies outside of a specified target enveloping area (HR) or if a deviation (D) between an actual variable (GI) and the corresponding target variable (GS) is unacceptably large, selected first and/or second cutting bodies (24a, 24b) are machined and/or removed by a laser device (35).

A rotary tool (21) working surface (23) includes a plurality of cutting bodies (24). The rotary tool (21) can be driven about a rotational axis (R). The actual enveloping surface (HF) of the working surface (23) is ascertained by an optical measuring arrangement (29). At least one other target variable (GS) is detected, which describes a microscopic parameter of the working surface (23). The actual variable (GI) corresponding to each specified target variable (GS) is detected by the measuring arrangement (29), and the deviation between the target variable (GS) and the actual variable (GI) is determined. If the actual enveloping surface (HF) lies outside of a specified target enveloping area (HR) or if a deviation (D) between an actual variable (GI) and the corresponding target variable (GS) is unacceptably large, selected first and/or second cutting bodies (24a, 24b) are machined and/or removed by a laser device (35).

An inner rotary retaining member has an annular outward rolling surface formed of part of a radially outward tapered surface centering on the central axis of a first rotary drive shaft. An outer rotary retaining member has an annular inward rolling surface formed of part of a radially inward tapered surface centering on the central axis of a second rotary drive shaft. The rolling surfaces are opposed to each other. A pocket that supports a workpiece such that the workpiece rotates and revolves as the retaining members rotate is formed at a portion of the carrier, the portion being positioned between the rolling surfaces. The central axis of the workpiece supported by the pocket is inclined relative to the central axis of the rotary drive shafts.

An inner rotary retaining member has an annular outward rolling surface formed of part of a radially outward tapered surface centering on the central axis of a first rotary drive shaft. An outer rotary retaining member has an annular inward rolling surface formed of part of a radially inward tapered surface centering on the central axis of a second rotary drive shaft. The rolling surfaces are opposed to each other. A pocket that supports a workpiece such that the workpiece rotates and revolves as the retaining members rotate is formed at a portion of the carrier, the portion being positioned between the rolling surfaces. The central axis of the workpiece supported by the pocket is inclined relative to the central axis of the rotary drive shafts.

In a method for pre-profiling a grinding tool, a device, in particular a gear grinding machine, for hard fine machining of workpieces and for pre-profiling grinding tools is provided, which includes a workpiece spindle for rotating a workpiece, a grinding spindle, which is feedable at least along an X-grinding-spindle-infeed-axis, for rotating a grinding tool, in particular a grinding worm or a grinding wheel, and a profiling device with a fixed first profiling plate. A grinding tool blank, in particular a grinding worm blank, is provided on the grinding spindle of the device. The device is brought into a profiling configuration. The grinding spindle is fed until the grinding tool blank is operatively connected to the first profiling plate. Finally, the grinding tool blank is pre-profiled.

A method includes depositing a slurry onto a polishing pad of a chemical mechanical polishing (CMP) station. A workpiece is polished and polishing by-products and slurry are removed from the polishing pad by a vacuum head. A CMP apparatus includes a polishing pad configured to rotate during a CMP process. The apparatus also includes a slurry dispenser configured to deposit a slurry onto a polishing surface of the polishing pad. The apparatus further includes a momentum vacuum assembly including a slotted opening facing the polishing surface of the polishing pad. The apparatus also includes a first suction line coupled to an upper portion of the momentum vacuum assembly and leading to a first vacuum source, the first suction line configured to transport polishing products which have been removed from the polishing pad through the slotted opening.