新型互補式金氧半感測晶片應用於液體熱傳導係數之量測

Abstract

This study aims to design and develop a CMOS sensor chip for measuring thermal conductivity of liquids. The CMOS sensor chip is realized by VIS 0.5 μm 2P3M CMOS process with maskless post-CMOS micromachinings. The procedure used to measure thermal conductivity of liquids here is utilized to replace conventional methods which require a great deal of specimen and cost a long measurement time. The measurement system consists of a heater at the center, four pairs of temperature sensors, specimen of liquid drop and a cavity for thermal insulation. Once a heat flux is applied by the heater, it will cause temperature variations of the sensor. Different kinds of tested liquids will result in different temperature variations of the sensor. The temperature variation will correspond to the resistance variation of temperature sensors. Four kinds of liquids are used to measure in the thesis. The conclusions of experiment results are as follows: a liquid with higher thermal conductivity results in a smaller resistance variation of the temperature sensor. In addition, an experiment system will have a larger time constant as a liquid with higher thermal conductivity is tested. Thermal conductivities of other liquids could be measured as well based on a relation between thermal conductivity and time constant was established by the measuring procedure in the thesis.