As multilayer copper wiring is constructed, the planarized topographical features of the copper layers become increasingly important. One of the most promising techniques for surface planarization is chemical mechanical polishing (CMP). CMP is a highly efficient process due to the varied chemical and physical properties of the slurry, which is composed of abrasive particles suspended in a chemical solution. In this study, polyglycerol-functionalized nanodiamond (ND-PG) is proposed as a suitable abrasive for copper CMP. As ND-PG has good features such as small diameter, high water solubility, and no risk of metallic contamination, it is available for next-generation design rules of semiconductors. In this paper, the planarization performance of ND-PG is investigated. It is experimentally confirmed that a slurry containing ND-PG improves the RMS surface roughness from 20 to 1 nm.

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Micro-V-groove cutting of cobalt-free tungsten carbide using two types of V-shaped diamond tool is performed using a mist of zinc dialkyl-dithiophosphate (ZnDDP) as a lubricant. The two types of tool tested are 1) monocrystalline diamond and 2) polycrystalline diamond made from diamond crystals approximately 30 nm in size. The geometry of the V-groove cutting process is theoretically investigated and the relationships between V-groove angle, original rake angle, and effective rake angle are clarified. Through the cutting experiments, the effects of diamond types and rake angle on tool wear characteristics are explained. When rake angle is set to 0°, tool chipping occurs frequently for both types of diamond tool, even when ZnDDP is supplied. However, tool wear is minimized at a rake angle of -30° for polycrystalline diamond.

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The stress distribution generated in non-alkali sheet glass during mechanical scribing was numerically analyzed by the finite element method (FEM). After investigation of the effect of element size on calculated results for static contact between the scribing wheel and glass, the stress distribution between the traveling wheel and glass was analyzed. The results indicated that the stress distribution in glass varied dynamically with wheel rotation. A comparison between experimental and numerical results suggested that the cleavage surface quality was markedly influenced by stress fluctuation generated in glass.

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Although ultrasonic processing is suitable for materials with high hardness and high brittleness, such as ceramic materials, it has a slow fault compared with a general cutting processing speed. The ultrasonic processing of ZrO₂ was irradiated with a CO₂ laser as preliminary processing to overcome this fault. In addition, ultrasonic processing was performed after laser irradiation, and changes in processing depth, dimensional processing accuracy, and tool wear were investigated. The results indicated that optimal laser irradiation conditions existed with the ultrasonic processing. It was the laser output 30W with air assistant gas, the scanning rates 6000 mm/min, as the machining depth was 1000μm.

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