Researcher(s)
- Nicolas Bailey, Mechanical Engineering, University of Delaware
Faculty Mentor(s)
- Joseph Feser, Mechanical Engineering, University of Delaware
Abstract
Time Domain Thermoreflectance (TDTR) has emerged as a powerful non-destructive technique for characterizing thermal properties of materials and interfaces in the field of thermal management. In this study, we present the application of TDTR to measure the thermal resistance of thermocompression bonded interfaces, which play a crucial role in microelectronic and optoelectronic device fabrication.
Thermocompression bonding is widely employed in the assembly of microchips, sensors, and other microscale devices due to its ability to produce strong and reliable interconnections. Understanding the thermal properties of these interfaces is vital for optimizing device performance and reliability. However, conventional techniques for characterizing thermal resistance in thermocompression bonded interfaces suffer from limitations in accuracy, sensitivity, and ease of implementation.
TDTR overcomes these limitations by providing a highly precise and contactless method to probe the thermal properties of thin films and interfaces. The principle of TDTR involves illuminating the sample surface with two pulsed laser beams, where one serves as a pump and the other as a probe. The pump laser generates a transient temperature rise in the sample, and the probe laser monitors the resulting change in reflectance of the material being measured. By analyzing the temporal evolution of the reflectance change, the thermal conductivity and interface thermal resistance can be deduced.
In this work, the successful application of TDTR was demonstrated to measure the thermal resistance of thermocompression bonded Au-Au interfaces. This was done with the hopes of providing some characterization to the performance of these devices and to illustrate whether the thermocompression bonding was successful in providing a path for heat to flow through the system. The results provide valuable insights into the optimization of these devices for enhanced device reliability and thermal management.
The non-destructive nature of TDTR makes it an attractive tool for in-situ and real-time measurements, opening up possibilities for future studies on the dynamic behavior of thermocompression bonded interfaces under varying operational conditions. Additionally, the presented approach can be extended to evaluate the thermal properties of other bonded interfaces and advanced materials systems, broadening the scope of its application in various industries and research fields. Overall, the integration of TDTR in the characterization of thermocompression bonded interfaces showcases its potential as a valuable technique for advancing microelectronic and optoelectronic device technologies.