Investigation on the fabrication of dicing blades with different sintering methods for machining hard-brittle material wafers

Abstract

Hard-brittle materials applied in various micro-electromechanical systems should be sliced into miniature and microparts often with complex microstructures. However, it is difficult for bladed dicing to machine those materials without damage because of their hard and brittle properties. This article presents innovative design and fabrication of dicing blades and the associated dicing process optimization, particularly by focusing on the blade wheel fabrication through sintering methods including traditional hot press sintering, vacuum sintering and spark plasma sintering. Four key parameters, namely, the radial wear of the dicing blade, the current of relay, the number of chips larger than 50 μm and the largest chip size, are employed to assess the cutting performance of dicing blades fabricated. The analysis and experimental results indicate that the spark plasma sintering method achieves the lowest number of chips and the smallest chip size due to its rapid spark between metal particles during the sintering process. The spark plasma sintering method can also produce a granular microstructure with sufficient porosities, which results in uniform bonding strength of diamond abrasive grits within the dicing blade. For the dicing process parameters, the back cutting depth has the most obvious influence on the dicing blade tool life, cutting current and slicing damages, while the feed rate is ranked the next. The least influencing parameter is the dicing spindle rotational speed.