Malits Maria, Nemirovsky Yael
Department of Electrical Engineering, Technion-Israel Institute of Technology, Haifa 3200003, Israel.
Sensors (Basel). 2017 Jul 29;17(8):1739. doi: 10.3390/s17081739.
This paper reviews and compares the thermal and noise characterization of CMOS (complementary metal-oxide-semiconductor) SOI (Silicon on insulator) transistors and lateral diodes used as temperature and thermal sensors. DC analysis of the measured sensors and the experimental results in a broad (300 K up to 550 K) temperature range are presented. It is shown that both sensors require small chip area, have low power consumption, and exhibit linearity and high sensitivity over the entire temperature range. However, the diode's sensitivity to temperature variations in CMOS-SOI technology is highly dependent on the diode's perimeter; hence, a careful calibration for each fabrication process is needed. In contrast, the short thermal time constant of the electrons in the transistor's channel enables measuring the instantaneous heating of the channel and to determine the local true temperature of the transistor. This allows accurate "on-line" temperature sensing while no additional calibration is needed. In addition, the noise measurements indicate that the diode's small area and perimeter causes a high 1/ noise in all measured bias currents. This is a severe drawback for the sensor accuracy when using the sensor as a thermal sensor; hence, CMOS-SOI transistors are a better choice for temperature sensing.
本文回顾并比较了用作温度和热传感器的互补金属氧化物半导体（CMOS）绝缘体上硅（SOI）晶体管和横向二极管的热特性和噪声特性。给出了被测传感器的直流分析以及在较宽温度范围（300K至550K）内的实验结果。结果表明，这两种传感器都需要较小的芯片面积，功耗低，并且在整个温度范围内都具有线性度和高灵敏度。然而，CMOS-SOI技术中二极管对温度变化的灵敏度高度依赖于二极管的周长；因此，需要对每个制造工艺进行仔细校准。相比之下，晶体管沟道中电子的热时间常数短，能够测量沟道的瞬时发热并确定晶体管的局部真实温度。这使得能够进行精确的“在线”温度传感，而无需额外校准。此外，噪声测量表明，二极管的小面积和周长在所有测量的偏置电流下都会导致较高的1/f噪声。当将该传感器用作热传感器时，这对传感器精度是一个严重的缺点；因此，CMOS-SOI晶体管是温度传感的更好选择。
