Abstract
As the practical application of 3D heterogeneous chip integration progresses rapidly, the demand for Chip-on-Wafer (CoW)
bonding is increasing. This paper examines recent research trends in CoW bonding and discusses current technologies and associated
issues. In addition, this paper introduces the authors’ three core technologies for narrower pitch bonding. First key technology is a
method to quantify the thermal fluctuation behavior in thermal compression bonding. The second is a new cutting-edge micro bump
formulation process using a combination of thermal imprinting and photolithography. The third is a in-situ determination system of
the quality of micro-bump bonding process using the 2-axis micro strain sensors embedded in the chip.
