Exemplary methods of manufacturing a semiconductor cover wafer may include sintering aluminum nitride particles into a substrate characterized by a thickness and characterized by a disc shape. The methods may include grinding a surface of the substrate to reduce the thickness to less than or about 2 mm. The methods may include polishing the surface of the substrate to reduce a roughness. The methods may include annealing the substrate at a temperature of greater than or about 800° C. for a time period of greater than or about 60 minutes.

A grinding wheel is mounted on a tip end of a spindle and the grinding wheel grinds a workpiece according to rotation of the spindle. The grinding wheel includes an annular base, and a plurality of grindstone sets disposed in an annular manner on one surface side of the base along a circumferential direction of the base. Each of the plurality of grindstone sets has a first grindstone and a second grindstone having a self-sharpening capability lower than that of the first grindstone, such that the first grindstone and the second grindstone are adjacent to each other in a predetermined orientation in the circumferential direction of the base, and a predetermined interval larger than an interval between the first grindstone and the second grindstone in the circumferential direction of the base is provided between adjacent ones of the grindstone sets.

A creep feed grinding apparatus includes a chuck table, a grinding unit having a spindle and a grinding wheel mounted on a lower end of the spindle, the grinding wheel including a plurality of grindstones disposed in an annular array on a surface of an annular base, the grindstones following an annular track upon rotation of the spindle, a moving mechanism for moving the chuck table and the grinding unit relative to each other along a predetermined direction perpendicular to the longitudinal axis of the spindle, and a bottom surface state adjusting mechanism for adjusting states of bottom surfaces of the grindstones by cleaning and/or correcting the bottom surfaces of the grindstones. The bottom surface state adjusting mechanism is positioned outside of a relative movement area of the chick table in which the chuck table and the grinding unit are moved relative to each other by the moving mechanism.

A grinding apparatus has a grinding wheel fastened to a mount disk connected a spindle by a plurality of bolts. The mount disk has at least three threaded holes and a plurality of protrusions protruding from a mount surface thereof. Each of the bolts includes an externally threaded shank, a neck coupled to the externally threaded shank, and an engaging flange coupled to the neck and extending radially outwardly. The grinding wheel includes an annular open hole defined in a mating surface of an annular base for mating with the mount surface, an annular slot that is wider than the annular open hole and is fluidly connected to the annular open hole, at least three insertion holes in the annular open hole for allowing the engaging flange to be inserted into the annular slot, and a plurality of protrusion insertion holes for receiving the engaging flanges of the bolts.

A method for machining a ceramic workpiece includes providing a sonotrode that has a transducer and a horn arranged along an axis, and the horn has helical slots and terminates at a tip, bringing the tip into proximity of the ceramic workpiece and providing an abrasive media to a work zone around the tip, using the transducer to produce ultrasonic vibration that axially propagates down the horn and causes axial vibration at the tip, and the helical slots convert a portion of the axial vibration to torsional vibration at the tip, and the axial vibration and the torsional vibration causing the abrasive media to abrade the ceramic workpiece in the work zone and thereby remove a localized portion of the ceramic workpiece.

A method for machining a ceramic workpiece includes providing a sonotrode that has a transducer and a horn arranged along an axis, and the horn has helical slots and terminates at a tip, bringing the tip into proximity of the ceramic workpiece and providing an abrasive media to a work zone around the tip, using the transducer to produce ultrasonic vibration that axially propagates down the horn and causes axial vibration at the tip, and the helical slots convert a portion of the axial vibration to torsional vibration at the tip, and the axial vibration and the torsional vibration causing the abrasive media to abrade the ceramic workpiece in the work zone and thereby remove a localized portion of the ceramic workpiece.

A method of cleaning and polishing a backside surface of a semiconductor wafer is provided. The method includes placing an abrasive brush, comprising an abrasive tape wound around an outer surface of a brush member of the abrasive brush, on the backside surface of the semiconductor wafer. The method also includes rotating the brush member to polish the backside surface of the semiconductor wafer by abrasive grains formed on the abrasive tape and to clean the backside surface of the semiconductor wafer by the brush member which is not covered by the abrasive tape.

A machine featuring a treatment tool that grinds a surface to a desired profile, imparts a desired roughness to that surface, and removes contamination from the surface, the machine configured to control multiple independent input variables simultaneously, the controllable variables selected from the group consisting of (i) velocity, (ii) rotation, and (iii) dither of the treatment tool, and (iv) pressure of the treatment tool against the surface. The machine can move the treatment tool with six degrees of freedom.

The occurrence of breaking and chipping at the wafer peripheral edge of a bonded wafer obtained by bonding a lamination wafer on a support wafer is suppressed. A lamination wafer to be bonded to a support wafer includes a large-diameter portion made of a silicon wafer whose peripheral edge is chamfered and a small-diameter portion, whose diameter is smaller than that of the large-diameter portion, formed on the large-diameter portion concentrically and integrally with the large-diameter portion, and the small-diameter portion includes a straight body portion whose side surface is perpendicular to the wafer surface, and a neck portion whose side surface is oblique with a predetermined angle to the wafer between the straight body portion and the large-diameter portion, and the small-diameter portion is formed such that the upper face of the straight body portion is to be bonded to the support wafer.

In an embodiment, a method includes: performing a self-limiting process to modify a top surface of a wafer; after the self-limiting process completes, removing the modified top surface from the wafer; and repeating the performing the self-limiting process and the removing the modified top surface from the wafer until a thickness of the wafer is decreased to a predetermined thickness.