Abstract: A method and apparatus for measuring the surface temperatures of wire-bonded semiconductors and the like for preparing thermal maps include a conventional ultrasonic wire bonding machine adapted for mounting a fluorescence-decay temperature sensor in the capillary holder. A trigger box circuit is provided to trigger a temperature measurement based on initiation of an electrical voltage signal from the ultrasonic bonding controller. A computer is provided for coordinating the stage control and temperature measurements, and for collating and plotting the temperature, time and location indications as thermal maps and other displayed/printed correlations.