高解析度之新型CMOS流速感測器之開發與研究

Development of a Novel High Resolution CMOS Flow Sensor

鄧雅薇(Ya-Wei Deng)

指導教授 ： 陳炳煇

國立臺灣大學/工學院/機械工程學研究所/碩士(2005年)

https://doi.org/10.6342/NTU.2005.02646

摘要

本論文主要的研究內容是以CMOS製程為基礎之流速感測器開發，主要應用在監測散熱模組中流場的速度，以觀察散熱模組是否無法達到足夠的散熱效果。此流速感測器結構與信號處理電路之大小為2 mm2，其結構包含一個位於感測器中央之微加熱器、以及四邊圍繞以熱電耦組成之溫度感測器，當給予電壓時，加熱器中心產生一個漂浮的熱氣團，一旦有外界的氣流擾動，此氣團會隨著氣流漂移，造成加熱器四周之溫度感測器感受到不同的溫度，藉由熱電耦的原理，X方向與Y方向之溫度感測器產生溫度差而輸出電壓差值，依據電壓值大小可達到量測氣流流速的目的。本研究針對自然對流問題、傾斜角度問題做出探討，也克服了此結構本身外封裝邊緣產生的效應，找出其最佳的角度應用範圍，以及電壓與氣流流速間之關係。此流速感測器之敏感度可達到0.7 mV/ (m/s)，速度量測解析度為0.001 m/s，輸出電壓與流速之間亦具有相當線性之量測結果，此流速感測器之流速量測範圍約為0.1 m/s到3.6 m/s之間。

關鍵字

CMOS流速感測器 ； 微加熱器 ； 熱電耦 ； 熱氣團 ； 速度量測解析度

並列摘要

The study develops an integrated CMOS flow sensor applied in monitoring the flow condition in thermal module. The flow sensor has a high resolution in low speed air flow field. This sensor includes micro structures and mixed signal processor in 2 mm square chip die size fabricated by the standard CMOS process. The microstructures of sensor consist of a polysilicon micro heater and the thermopiles array. The center micro heater encircled by the temperature sensors generates the thermal plume. As the sensor is positioned against the flow, the thermal plume will be pushed towards to the temperature sensors array and the temperature difference can be converted into the voltage to determine the air flow speed. The flow sensors arrayed in four sides gives both output voltages in x-direction and y-direction, and the sensor makes splendid accomplishments as it is operated under impinging flow. Combining signal output from two perpendicular sensors, the module can make three components of velocity measurement. The sensitivity of the flow sensor can be indicated as 0.7 mV/ (m/s) under impinging flow and 0.001 m/s velocity measurement resolution is achieved. The air flow speed ranges from 0.1 to 3.6 m/s.

並列關鍵字

CMOS flow sensor ； Polysilicon micro heater ； Thermopiles array ； Thermal plume ； Velocity measurement resolution

參考文獻

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