TAIKO wafer ball attach

Ball attach on ultra-thin 200 mm TAIKO wafers is considered a challenge but it can be mastered. The TAIKO wafer grinding concept is based on the thinning of an inner area of a silicon wafer leaving an outer ring as stiffening frame for wafer handling without an additional carrier [1]. The process development methodology for a near industrial TAIKO wafer balling pilot line is described. A phased process development methodology was applied with different residual wafer thicknesses, wafer ball diameters and balling pitches to check yield affecting topics and process throughput.