微量移液器取樣體積定量感測器開發

本研究開發微機械結構系統之速度感測器應用於微量移液器偵測取樣容積定量，微結構速度感測器中心位置利用多晶矽做成微發熱器，微發熱器四周是溫差電堆陣列溫度感知器，感測速度利用微發熱器在微結構中產生熱氣泡，由移液器活塞移動驅使微熱氣泡變形，四周的溫度感知器偵測到不同溫度差，此溫差即為速度之變化，由此來計算出液滴管內溶液體積，其微結構速度感測器製造過程由標準金屬氧化半導體製程做材料的沉積，再利用蝕刻技術完成凹槽絕熱層之立體結構，速度感測器元件大小為2mm方形構造，其中包含了微結構系統及訊號電路，校正結果此速度感測器的特性靈敏度為1V/m/s、速度測試範圍在0.02-0.2 m/s以及線性誤差在5.3%範圍內，此速度感測器具有高解析度、高靈敏度及具線性等特性，將微結構速度感測器應用於微量移液器可顯示出取樣體積，實驗驗證在20μL的取樣實驗中可以使誤差在2.5%範圍內，並且控制操作者使用在正當模式下操作，從DNA增生實驗結果中可以看出利用此微量移液器所進行之實驗可以更穩定的增生DNA增生實驗。

關鍵字

微機械結構系統；速度感測器；微量移液器

並列摘要

The study developed an integrated MEMS flow sensor applied in detecting the volume of samples in Pipet. The microstructures of the sensor consist of a polysilicon micro heater and a thermopiles array. The centered micro heater bar encircled by temperature sensors generates the heat 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 voltage to determine the air volume flow rate through the tip. This sensor includes micro structures and mixed signal processor in 2 mm square chip die size fabricated by the standard CMOS process. A square heater source is located at the center of square polysilicon thin film with a cavity underneath. The cavity provides good thermal insulation when electric power is supplied to the heater. The sensitivity of the flow sensor can be indicated as 1 V/ (m/s). The air flow speed ranges from 0.02 to 0.2 m/s. The linear error is less than 5.3%. The flow sensor has a high sensitivity and linear in low speed air flow field. The experiment proves that can make the error in 2.5% of the ranges in the sample experiment of 20μL. The operator can reject improper pipetting according the readings of the pipetting error sensor. HBV quantification experiments were carried out in this study. The results show that accurate DNA quantification and high reproducibility of experiments can be obtained by the pipetting error sensor feedback.

並列關鍵字

MEMS ； flow sensor ； Pipet

參考文獻

[12]鄧雅薇，高解析度之新型CMOS流速感測器之開發與研究，碩士論文，國立臺灣大學機械工程研究所，台北，2004。

[1]N.T. Nguyen, "Micromachined flow sensors," Flow Measurement and Instrumentation, 1997, p 7-16.

[2]M. Elwenspoek and R. Wiegerink, "Mechanical Microsensoors," 2000, Springer.

[3]A. F. P. Van Putten and S. Middelhoek, "Integrated silicon anemometer," Electronic Letters, 1974, 10, pp. 425-426.

[4]G. Stemme, "A monolithic gas flow sensors with polyimide as thermal insulator," IEEE Trans. Electron Devices, 1986, ED – 33 , pp.1470 - 1474

國際替代計量

微量移液器取樣體積定量感測器開發

未授權

主題瀏覽