Abstract: Provided is a film forming apparatus in which a thin film can be formed with a good coverage on the inner surface of a hole with high aspect ratio by preventing the negative electric charges from getting concentrated on the substrate edge portion at the time of etching processing. The film forming apparatus is provided with: a vacuum chamber in which a target is disposed; a stage for holding a substrate inside the vacuum chamber; a first electric power for applying predetermined electric power to the target; and a second electric power for applying AC power to the stage. The film forming apparatus performs: film forming processing in which the target is sputtered by applying electric power to the target by the first electric power; and etching processing in which a thin film formed on the substrate is etched by applying AC power to the stage by the second electric power.

Abstract: A production method for a semiconductor wafer is provided in which semi-fixed abrasive grain grinding with free abrasive grains reduces minute surface undulations generated by wire saw slicing or double disc grinding as well as simplifying conventional semiconductor wafer fabrication process steps. A production method for a semiconductor wafer characterized by conducting a slicing process, then a beveling process, an etching process, and a one side or double side polishing process, wherein a semi-fixed abrasive grinding process using a porous polishing pad and free abrasive grains is conducted after the slicing process.

Abstract: An aqueous grinding fluid has compositions mainly consisting of 40.0-95.0 wt. % a polyalcohol and/or a polyalcohol derivative, 5.0-50.0 wt. % water, 0.1-3.5 wt. % bentonite, 0.1-5.0 wt. % cellulose and weight %, 0.5-10.0 wt. % mica and optionally a small amount of a surfactant or polar solvent. Bentonite, cellulose and mica are preferably added with such combination to adjust a viscosity of a slurry to 150-300 mPa.second as a value measured by a rotating cylinder type viscometer. The aqueous suspension is nonflammable and stabilized in dispersiveness and settleability-proof of abrasive grits as well as a viscosity for a long time, and facilitates washing and cleaning of sliced wafers and a grinding machine without radiation of stinks.

Abstract: Slurry useful for wire-saw slicing has viscosity adjusted to 400-700 mPa·second at a shear speed of 2/second and of 50-300 mPa·second at a shear speed of 380/second. The viscosity of slurry is measured using a cone and plate type viscometer which can measure viscosity at different shear speeds. Since the slurry sufficiently flows into inner parts of grooves formed in an ingot and consumed for wire-saw slicing due to the viscosity controlled in response to the shear speed, the ingot can be efficiently sliced to wafers or discs.

Abstract: A newly proposed wire cleaning apparatus used for removing slurry from a wire, which reciprocatively travels between a slicing chamber and a wiring chamber. The wire cleaning apparatus has a couple of multigrooved guide rollers 41, 42 rotatably provided at a cover 30. A slurry receiver 20 is detachably attached to the cover 30. A centrifugal force is generated during repeated reciprocative movement of the wire 5 between the multigrooved guide rollers 41 and 42. Slurry is shaken off from the wire 5 by the centrifugal force and gathered in the slurry receiver 20. Removal of the slurry is accelerated by spraying a cleaning liquid W at the same time. Introduction of the cleaning liquid W into the slicing chamber is inhibited by on-off control of the cleaning nozzles 41, 42 in response to a travelling direction of the wire 5.

Abstract: An ingot 9 is sliced to wafers by a wire 5 which travels around grooved rollers 1 to 3. A tension applied to the wire 5 is detected by tension sensors 21, while vertical displacement of dancer rollers 19 is detected by position sensors 20. At least one of a fluctuation gap of the tension, a fluctuating velocity of the tension, an acceleration of the fluctuation, vertical movement of the dancer rollers 19, a velocity of the vertical movement and acceleration of the vertical movement is calculated from the detection results, and compared with a threshold in a calculating circuit 23 to judge a sign predicting abnormal increase of the tension. When the predicting signal appears, a command signal is outputted from the calculating circuit 22 to a controller 23 to stop operation of a wire-sawing machine or to relax the wire 5. Since rupture of the wire 5 is prevented in bud, a wire-sawing machine is efficiently driven for slicing the ingot 9 with a high productivity.

Abstract: If something goes wrong with a wire saw, a personal computer outputs a dial signal to a modem, which dials a calling number of a pager carried by an operator through a telephone system. The sound of the pager notifies the operator of the abnormality of the wire saw even if he or she is not in the vicinity of the wire saw.

Abstract: A sensor measures a displacement of a sensor, and a control part of a wire saw calculates a sliding load in accordance with the measured displacement and an initial tension of the wire. Then, the control part compares the calculated cutting load with a preset reference value, and controls an ingot feed speed for a drive unit of a workpiece feed table in accordance with the results of the comparison.

Abstract: An ingot slicing method and apparatus is disclosed. An ingot is sliced by a wire saw having a wire wound over a plurality of grooved rollers at a predetermined pitch. The ingot is secured to a holder and then pressed onto the wire which is carried along one direction or reciprocatively carried over a plurality of grooved rollers. The holder is shifted along one direction parallel to an axis of the grooved rollers until about a half section of the ingot is sliced. The holder is shifted along an inverse direction during slicing the remainder of the ingot. Thus, a wafer sliced off the ingot has a bowed shape corresponding to a locus of movement of the holder.

Abstract: A wafer 1 has a chamfered edge 2 polished to specular glossiness, and a laser mark for indication of crystal orientation is put on the chamfered edge 2. Another laser mark 4 for indication of specification, production number, identification, etc. may be carved as a bar code on the chamfered edge 2. These marks 3, 4 are carved on the chamfered edge 2 by laser marking which does not put any harmful influences on the wafer 1.

Abstract: A shallow notch 1 as a tentative mark is engraved on a periphery of an ingot at a position corresponding to a predetermined crystal orientation in the step of grinding the periphery of the ingot. After the ingot is sliced to wafers, a mark 2 for indication of a crystal orientation is carved on a sliced wafer at a position determined on the basis of the notch 1 by laser marking. Thereafter, the wafer is chamfered to a round shape, and the notch 1 is removed by the chamfering. Since a part where the mark 2 shall be carved is determined on the basis of the notch 1, the mark 2 is efficiently carved on the wafer without the necessity of subjecting each wafer to an X-ray analyzer.