栅极天线和NMOS耦合的CMOS太赫兹热探测器的设计与测试

Design and Measurement of CMOS Terahertz Thermal Detector with Gate-antenna and NMOS Transistors

设计了一种在室温工作的太赫兹热探测器.探测器由片上天线和温度传感器耦合而成.天线由NMOS温度传感器的栅极组成,吸收入射的太赫兹波将其转化为焦耳热,生成的热量引起的温度变化由温度传感器探测.整个探测器的探测过程分为电磁辐射吸收、波-热转换、热-电转换三个过程,并分别进行了建模分析,仿真得到天线吸收率为0.897,热转换效率为165K/W,热电转换效率为1.77mV/K.探测器基于CMOS 0.18μm工艺设计,工艺处理后将硅衬底打薄至300μm.探测器在3THz太赫兹环境下,入射功率为1mW时,电压响应率仿真值为262mV/W,测试值为148.83mV/W.

A structure of thermal terahertz detector working at room temperature was proposed.The detector is consisted of an on-chip antenna and a temperature sensor.The antenna made of gates of the temperature sensor absorbs incident terahertz wave and converts it to Joule heat.The heat-generated temperature rise is then detected by the temperature sensor.The working flow of the detection can be divided into three parts: electromagnetic absorption,thermal-heat conversion and thermal-electrical conversion.Modeling and simulation of every process are presented.The simulated Antenna absorptivity is 0.897,the heat transfer efficiency is 165 K/W and the thermoelectric conversion efficiency is 1.77 mV/W.The detector is designed based on 0.18 μm CMOS technology with post-process thinning the silicon substrate to 300 μm.Its simulated voltage responsivity is 262 mV/W at 3 THz frequency,while the tested value is 148.83 mV/W under the incident power of 1mW.