Enhanced Sensitivity of GaN-Based Temperature Sensor by Using the Series Schottky Barrier Diode Structure

Temperature sensor using series GaN Schottky barrier diode (SBD) with TiN anode was fabricated and evaluated extensively. The diode presents good characteristics in a wide temperature range from 25 °C to 200 °C. The temperature dependent forward voltage of the conventional 8-finger SBD at a fixed current shows good linearity, resulting in a sensitivity of approximately 1.14 mV/K. On the other hand, the series SBD with two 8-finger diodes enhances the sensitivity by nearly two times. The enhancement in temperature sensitivity is interpreted using a series model, with the obtained parameters are comparable with the 8-finger SBD.