氧電漿對氧化銦薄膜電晶體的影響

The Effect of Oxygen Plasma on the Performance of Indium Oxide Thin Film Transistors

薛云婷(Yun-Ting Hsueh)

指導教授 ： 吳孟奇 ； 朱治偉

國立清華大學/電機資訊學院/光電工程研究所/碩士(2009年)

摘要

薄膜電晶體是最早被發明的場效電晶體，原本被期望可以取代真空管應用於電算機中，但是後來逐漸被性能更優越的金屬-氧化物-半導體場效電晶體取代，直到新應用的出現才又受到重視，這個新應用主要是作為液晶顯示面板中畫素的切換開關，尤其是大尺寸的顯示面板當中更顯得重要。在本論文中，探討以熱蒸鍍反應技術沈積，並以氧電漿方式氧化氧化銦薄膜，實現在二氧化矽為閘極介電層的氧化銦薄膜電晶體。比起先前用高溫回火來氧化的氧化銦，氧電漿氧化只需在室溫底下即可達到氧化效果，較不耗時，能夠簡化製程及實現可撓性軟性電子的應用。在此實驗中，我們分別改變氧電漿的功率以及氧電漿氧化的時間去探討對氧化銦電晶體電性的變化，在氧電漿功率1000瓦氧流量50sccm氧化時間為90分鐘時，其氧與銦的比例最為接近3：2即三氧化二銦，此時場效電子遷移率約為0.32cm2/Vs，而打開與關掉的電流開關比約為106，隨著氧電漿氧化時間的增加，氧化程度越深，打開的電流與關掉的電流隨之降低，臨界電壓也越往正電壓偏移，
因此我們可以簡單的利用氧電漿去控制氧化銦薄膜電晶體的電性。

關鍵字

金屬氧化物 ； 氧電漿 ； 氧化銦 ； 電晶體

並列摘要

The thin-film transistors (TFTs) is the first field-effect transistor, and it was expected to substitute for the vacuum tube applied in the computer. But the TFT was replaced gradually by the Metal-oxide-semiconductor field-effect transistor which has superior performance. The TFT was not paid much attention until the appearance of new application, which was the switch of pixels in LCDs, and it was important especially LCDs with large size. In the thesis, thin-film transistors (TFTs) of indium oxide were fabricated on SiO2 gate dielectric and using reactive thermal evaporation process of high purity oxygen then oxygen plasma treatment to oxidize the indium oxide thin film. Compares with the indium oxide which oxidizes with the high tempering annealing, the advantage of oxygen plasma oxidation just only need under the room temperature. And it can simplify the fabrication process and realize flexible electronic with various thin-film transistor application.
In this experiment, we change the oxygen plasma power and the oxidized time to discuss the performance of the indium oxide transistors. When the condition of oxygen plasma was 1000 W, 50 sccm and oxidation time was 90 minutes, the proportion of oxygen and the indium most is close to 3:2. The field effect electronic mobility approximately is 0.32cm2/Vs, the on/off ratio of the device is 106. The electronic characteristic of indium oxide thin film transistor was found to be a strong function of the plasma treatment time and power. Therefore we may the simple use oxygen plasma control the indium oxide thin film transistor's properties.

並列關鍵字

metal oxide ； oxygen plasma ； indium oxide ； transistor

參考文獻

[4] R. E. Presley, D. Hong, H. Q. Chang, C. M. Hung, R. L. Hoffman, and J. F. Wager, Solid-State Electron. 50, 500 (2006).

[6] B. Yaglioglu, H. Y. Yeom, and D. C. Paine, Appl. Phys. Lett. 86, 261908 (2005).

[8] Y. L. Wang, Appl. Phys. Lett. 90, 232103 (2007).

[11] Dhananjay, C. W. Chu, Appl. Phys. Lett. 91, 132111 (2007).

[15] Practical Surface Analysis by Auger and X-ray Photoelectron Spectroscopy, 2nd edition, ed. M.P.Seah and D.Briggs, published by Wiley & Sons, 1992, Chichester, UK