| Summary: | 碩士 === 國立臺灣科技大學 === 機械工程系 === 102 === Multi-wire sawing process of ingot slicing is important for solar cell industry due to high production efficiency of brittle materials. However, the environmental pollution and complex clean-up operations of slurry wire sawing (SWS) need to be improved. Development of fixed abrasive wire saw or diamond wire sawing (DWS) is a positive trend that can overcome many shortcomings of SWS. This study aims to investigate the parametric effect of silicon chips produced from DWS of mono and polycrystalline silicon materials. This study establishes an efficient method for evaluating ductile and brittle maching mechanisms by calculating the specific cutting energy. It has been verified by comparing the estimating chip size and experimental results of silicon chips from developed model. Research methods focus on the calculating of specific cutting energy and removal volume of material of mono and poly crystalline by DWS. This study sets different process parameters to slice the monocrystalline silicon ingot by DWS to measure surface roughness and thickness variations of silicon wafer, and material removal ratio (MRR) for different process parameters. Meanwhile, this study makes a size estimating and measuring for silicon chips to distinguish the brittle or ductile maching condition. Finally, this study uses a modified wearing test machine of diamond wire and silicon ingot to perform wear experiments for calculating the grinding ratio to justify efficiency of diamond wire. The polycrystalline diamond is suited for electroplated diamond wire because its structure and self-dressing. When silicon ingot by DWS has feed rate at 0.01mm/min with specific cutting energy of 5.385 J/〖mm〗^3, ductile maching can be detected. Feed speed of silicon ingot of DWS sets at 0.3 mm/min with specific cutting energy of 0.179 J/〖mm〗^3, brittle maching can be found. Feed speed of silicon ingot of DWS sets at 0.1 mm/min with specific cutting energy of 0.538 J/〖mm〗^3, ductile maching and brittle maching can be both found. The diamond abrasive edge angle of 250 μm diameter of diamond wire can be found as average of 56.25 degrees. For monocrystalline silicon (100) and polycrystalline silicon, results of removal volume are obtained to 3.045 ×〖10〗^(-7) 〖mm〗^3/pcs and 4.099 ×〖10〗^(-7) 〖mm〗^3/pcs respectively. Different MRR between the estimated model and experimental results can developed in this study is about 1.9% to 2.7%. The reciprocating ratio is important in diamond wire lifetime of DWS. The material removal model extended and applied to slicing hard and brittle substrates of large sizes.
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