This paper discusses the MQL turning of ferrous metals—chromium-molybdenum steel SCM440H and pearlite malleable cast iron FCMP—using specified MQL turning tools. The tool holder has a branched oil hole that extends to two nozzles near the flank face and the rake face of the insert. Oil mist is thus supplied directly to both the flank–chip and rake–work contact zones. The effects of oil mist supplied to flank face and rake face were investigated. With regard to the cutting force in turning of SCM440H, the oil mist supplied to the rake face is more effective at low cutting speeds below 100 m/min. In contrast, the surface roughness of the workpiece is improved by the oil mist supplied to the flank face over a wide cutting speed range of 30–300 m/min. The tool temperature of SCM440H turning when the oil mist is supplied only to flank face is approximately 70°C lower than that in dry turning, whereas it drops by as much as 100°C when the oil mist is supplied to both faces.

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The flatness required for the surface of a 12″silicon wafer is becoming increasingly stringent. Therefore, a single-wafer-type CMP machine with oscillation speed control has been developed to achieve high flatness over the entire surface of large-sized wafers. Here, the experimental wafer profiles corresponded to the simulations with the flatness of a polisher profile of less than 5μm. The differences in contact distance for the radius on the polisher surface were calculated to control polisher degradation. The results showed that the differences became small with co-rotation and the same rotational speed using a circular polisher and in the case of counter-rotation using a ring polisher.

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A system was developed to achieve consistent micro-tool production and work-piece processing. It consists of an ELID grinding system and measurement equipment on a plane in a precision 4-axis processing machine. This system allows production of tools with high accuracy, and deviation of the tool can be reduced to 30 nm. The surfaces of the produced micro-tools were investigated using advanced analytical methods. Fracture strength of the micro-tools was evaluated by nano-indentation testing, and their surface chemical properties were analyzed by XPS. The results suggest that the surface of processed micro-tools had been strengthened by penetration and diffusion of oxygen atoms into the material, and subsequent oxidation.

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Reducing edge roll-off of silicon wafers is becoming increasingly important for uniform treatment near the wafer edge in both lithographic and CMP processes of semiconductor manufacture. Optimization of the wafer edge profile in terms of CMP uniformity during silicon wafer manufacturing is proposed as one method to reduce edge roll-off. FEM analysis is used to calculate the contact pressure on the wafer surface, and the removal rate is estimated based on the calculated contact pressure that is proportional to the removal rate in polishing of silicon wafers. As a result, reduction of the edge roll-off would be achieved by shortening the edge width of the wafer in the case of both double-sided and single-sided polishing. This conclusion does not depend on the Young's modulus of the polishing pad over the range of Young's modulus of 1-15 MPa, and does not depend on carrier thickness in double-sided polishing when the carrier thickness does not exceed the wafer thickness.

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