BaTiO3閘極離子場效電晶體元件特性模擬與分析之研究

Study on the Characteristic Simulation and Analysis of BaTiO3-Gate Ion-Sensitive Field Effect Transistor

邱保榮(Pao-Jung Chiu)

指導教授 ： 詹勳生

嶺東科技大學/資訊學院/資訊科技應用研究所/碩士(2011年)

摘要

離子場效應電晶體(Ion-Sensitive Field Effect Transistor, ISFET)相較於傳統離子感測電極具有尺寸小、響應快及與標準IC製程相容等特點。ISFET其結構相似於MOSFET，差異僅在於MOSFET之金屬閘極被參考電極/電解液/絕緣層(離子感測膜)所取代，且元件直接置於酸、鹼緩衝溶液中，使得感測膜表面產生電位變化，藉此電位變化，可感測出溶液中之離子濃度。

本論文係以非晶形鈦酸鋇(a-BaTiO3)薄膜，作為H+離子場效電晶體之閘極感測層，並以Mathematica軟體建立EIS與ISFET系統之數學模型，進行EIS結構之表面電壓與不同待測溶液特性曲線模擬、電容-電壓特性曲線模擬，及ISFET元件之電流-電壓特性曲線模擬、閘極電壓與不同待測溶液特性曲線模擬，以期了解BaTiO3-gate ISFET元件之理論特性。

關鍵字

BaTiO3 ； ISFET ； EIS結構 ； MIS結構 ； Mathematica

並列摘要

Ion-Sensitive Field Effect Transistor (ISFET) is better than ordinary ion selective electrodes, because it is smaller and faster and can be implemented in IC production. The structure of ISFET is similar to a standard MOSFET. The metal gate of MOSFET is replaced by reference electrode/electrolyte/sensing insulator. Also, the elements are directly placed in pH buffer solution in order to change the potential on sensing insulator surface. The ion concentration in the solution can be detected with the change of potential.

This study is based on an amorphous barium titanate (a-BaTiO3) thin film as a H+ ion field-effect transistor gate sensing layer, and the EIS and ISFET system mathematical model is created by Mathematica software. The surface voltage difference curves and capacitance-voltage characteristics are simulated on EIS structure. The current-voltage characteristics and gate-voltage curves also are simulated on ISFET device. The theoretical characteristics of the BaTiO3-gate ISFET device are understood.

並列關鍵字

BaTiO3 ； ISFET ； EIS structure ； MIS structure ； Mathematica

參考文獻

[1] P. Bergveld(1970), “Development of an ion-sensitive solid-state device for neurophysiological measurements”, IEEE Transactions on Bio-Medical Engineering, PP.70-71.

[2] William M. Siu and Richard S. C. Cobbold (NOV 1979), “Basic Properties of the Electrolyte-SiO-Si System: Physical and Theoretical Aspects”, IEEE Trans. Electron Devices, Vol. ED-26, NO. 11, PP. 1805-1815.

[3] David L. Harame, Luc J. Bousse, John D. Shott and Janmes D. Meindl(Aug 1987), “ION-Sensing Devices with Silicon Nitride and Borosilicate Glass Insulator”, IEEE Trans. Electron Device, vol. ED-34, NO. 8, PP. 1700-1707.

[4] Clifford D. Fung, Peter W. Cheung and Wen H. Ko(Jan 1986), “A Generalized Theory of an Electrolyte-Insulator-Semiconductor Field-Effect Transistor”, IEEE Trans. Electron Devices, vol. ED-33, NO.1, PP. 8-18.

[5] 武士香、虞惇、王貴華(1990)，”化學量傳感器”，感測器技術，第1期，PP. 57-62。