Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Wire Bonding Process Monitoring using Thermopile Temperature Sensor



Suman Shivesh, Michael Gaitan, Joshi Yogendra, George G. Harman


This work presents an approach to separate the thermal response due to ultrasonic excitation and ball deformation through a novel application of aluminum-polysilicon thermopile sensors under the bond pad. These integrated thermopile sensors measure temperature at a radial distance under the bond pad, in contrast to the previously reported average measurements over the bond pad interface or around the bond pad over a radial distance. The high sensitivity and signal-to-noise ratio of the sensor allow direct measurements of the signal, without any amplification or filtration. Transient temperature variations at two radial locations were obtained using two versions of thermopile sensor designs. The sensor response was interpreted using representative finite element thermal modeling for the process. Results from modeling reveal that the thermal response is a strong function of radial location. These results also reveal that the thermal response due to interfacial heating is significantly higher under the bond pad, as compared to that around the bond pad. This is in agreement with the experimental observations. Critical points on the temperature variation curve were identified.
IEEE Transactions on Advanced Packaging


Thermosonic ball bonding, CMOS compatible MEMS, thermopile temperature sensor, Seebeck effect, in-situ process monitoring.


Shivesh, S. , Gaitan, M. , Yogendra, J. and Harman, G. (2005), Wire Bonding Process Monitoring using Thermopile Temperature Sensor, IEEE Transactions on Advanced Packaging, [online], (Accessed April 24, 2024)
Created November 16, 2005, Updated October 12, 2021