An on-chip temperature sensor by utilizing a MOS tunneling diode

A simple metal-oxide-semiconductor (MOS) tunneling diode was demonstrated for being an integrated temperature sensor. The MOS diode equipped with a 21-Angstrom oxide was biased inversely at 1.8 V to monitor its substrate's temperature through gate current. The gate current increased more than 700 times when the diode was heated from 20 to 110 degreesC. An exponential fitting curve correlated the gate current and the substrate temperature. Moreover, characteristics of the diode were analyzed though C-V and I-1.8 (V)-n(i) curves. The good temperature response of the MOS tunneling diode might be useful in self-diagnosis or self-protection IC applications.