Characterization of MOSFET temperature sensors for on-chip dynamic thermal measurements

This work analyses the performance of MOSFETs as a temperature sensor for the measurement of AC on-chip thermal signals caused by a power-dissipating circuit under test (CUT). First, we characterize how the CUT-sensor thermal coupling depends on the frequency of the AC thermal signal and the CUT-sensor distance. Second, we characterize how the thermal sensitivity of the sensor depends on the bias current and the dimensions of the MOSFET. Such characterizations are carried out through a chip fabricated in CMOS technology with heaters and sensors integrated, and an infrared (IR) camera. The knowledge extracted from this work is expected to provide guidelines for a better design of thermal sensors intended for IC testing applications. © 2015 The Authors. Published by Elsevier Ltd. Peer-review under responsibility of the organizing committee of EUROSENSORS 2015.