The effect of the temperature on bondability and bonding process for wire bonding are investigated. Bondability is characterized by shear bonding strength and bonding process is represented by input and output power of ultrasonic transducer. A laser Doppler vibrometer and Labview software were used to record the velocity, voltage and current of transducer at different temperature settings. A K-type thermocouple sensor was used to measure the bonding temperature. Experimental results show that unsuccessful bonding happens at low temperature, and over bonding appears if the temperature is too high. Only when the temperature is at appropriate settings, can a stable and satisfied bondability be attained. The reason for this experimental observation is analyzed. By using a high resolution transmission electron microscope, the atom diffusion depth of Au-Ag bonding interface was measured and the result is about 200 nm. By using joint time-frequency analysis, the instantaneous characteristics of bonding process were observed completely and clearly. It is found that input and output ultrasonic power vs. time-frequency in a bonding process, including resonance frequency, harmonic components and amplitude of ultrasonic energy, vary along with the change of temperature settings.

Dynamical characteristics of PZT actuated transducer assembly are the key to reliable flip-chip bonding and basic understanding of metal interconnection. A systematic experimental observations and analysis clearly exhibit that, rich phenomena and effects like the negative cubic stiffness, dynamical coupling between transducer body and tool, velocity dropping and anomalous phase portrait of the die movement, may be explained by nonlinear features and non-parallel loading of transducer assembly onto its bonding area. It will be possible to explore their mechanism and effects to bonding quality by identifying and decoding them.

This study seeks to quantify the screw-fastening effect of the tool/transducer on wire bonding performance. Aluminum wire bonding experiments were performed on a laboratory test bench. Characterizations of bonding process through a wavelet analysis were used to study the relation between screw fastening, vibration behaviors and bond strength. The time-frequency plots were depicted for identifying un-modeled wire bonding dynamics. Finally some statistically time domain features were presented for further analysis.

The authors demonstrate that the ultrasonic vibration in flip chip FC bonding results in the generation of dislocations, and the atomic diffusion can be activated more easily along the dislocation lines which perform the fast diffusion channels, thus the dislocation diffusion is probably more prominent than the body diffusion during ultrasonic bonding. To minimize the intermetallic compound layer, the effectiveness of a different bonding approach is confirmed. Furthermore, an experiment-based mode of ultrasonic energy conversion was found that the ratio of up interface to down interface in ultrasonic FC bonding was about 2.3:1.

应力波的激光产生和检测，是一个受到各领域专家关注的、在无损检测和应用力学等方面有着极大应用潜力和研究兴趣的新兴领域。针对其力学方面、实验技术和应用前景等，本文对有关原理、方法、技术和实用进行了简要的归纳与总结。