Comprehensive Comparison of Integrated Temperature Sensors in CMOS-SOI Technology

This paper reviews the two most commonly used integrated temperature sensors available in CMOS-SOI technology: lateral PN diode and a standard MOSFET transistor. Both CMOS-SOI transistors and lateral diodes were designed and fabricated with a standard partially depleted CMOS-SOI 180nm process of IBM. Experimental results indicated that both lateral diodes and MOSFETs can be used to implement temperature sensors with high accuracy in room temperature and above, after a suitable calibration. It is shown that despite the linear behavior of both sensors the lateral diode has higher sensitivity, but a narrower useful temperature range. In addition, it is shown that lateral diodes exhibit much higher low frequency noise than standard MOSFETs, which can influence performance if the device is used as thermal sensor. The results of this study have impact on circuit design and may assist in choosing the optimal integrated temperature sensor or thermal sensor for SOI technology.