An inverse method to determine the temperature profile on a semiconductor power diode

A novel approach is developed to determine the nonuniform temperature profile on a semiconductor power diode. This technique requires the measurement of voltages and currents only. The temperature distribution is calculated using current-voltage-temperature relationships similar in form to the Shockley equation. Using these relationships, the temperatures across the junction are calculated as a best fit to the voltage and current measurements. The method offers an improvement over existing electrical measurement techniques since a complete temperature distribution is determined rather than a single junction temperature. This inverse method is tested using a power diode 18 mm in diameter and rated at 100 A. Preliminary measurements indicate that the method calculates peak junction temperature as accurately as existing techniques.<>