製備奈米碳管場效應電晶體整合於CMOS製程

Fabrication of Carbon Nanotube Field-Effect Transistor Compatible with CMOS Process

楊久進(Chiu-Chin Yang)

指導教授 ： 黃榮堂

國立臺北科技大學/機電學院/機電整合研究所/碩士(2008年)

摘要

本研究為製備一與標準CMOS製程相容之奈米碳管場效應電晶體並討論其製備方法與探討電子傳遞特性。本研究以低溫製備的方式結合介電泳力操控技術，光阻局部定義技術以及自我組裝單分子層表面改質技術製作出奈米碳管電子元件，探討其電子傳遞之物理特性。在實驗製作方面，當CMOS晶片完成製作後須經過溼式蝕刻之後製程以完成元件結構製作，接著利用介電泳力技術或者光阻局部定義技術配合表面改質技術將奈米碳管沈積並排列跨接於電極間隙之間，完成奈米碳管電子元件之製作。本文成功地利用CMOS製程與溼式蝕刻後製程製作出擁有相似於傳統p-type金氧半場效應電晶體特性之奈米碳管場效應電晶體以及電阻特性之奈米碳管電子元件，在擁有場效應特性之奈米碳管場效應電晶體其導通電流變化量約為2~5倍，而導通電流為2nA。此外，本研究使用無電鍍Ni/Au的方法將原本低功函數之TiN電極(~3.74eV)以高功函數之Ni/Au電極(~5.1eV)取代，能夠降低奈米碳管與接觸金屬之接觸電阻並降低金屬電極表面氧化的可能性，進而改善奈米碳管電子元件特性，提升”ON”電流值10倍以上。奈米碳管擁有優良的電子傳遞特性，製作為奈米碳管電子元件後，裸露在外的奈米碳管對於外界環境相當靈敏，非常適合用來做為感測元件，並利用本研究所製作之奈米碳管電子元件與CMOS製程相容之特性結合訊號處理電子電路以實現達到單晶片(SoC)之目的。

關鍵字

奈米碳管 ； 奈米碳管電晶體 ； 介電泳力 ； 自我組裝單分子層 ； 互補式金屬氧化半導體

並列摘要

The main objectives of this thesis aim to fabricate Carbon nanotube field-effect transistors (CNTFETs) combined with standard CMOS process. In this thesis, we will discuss the properties and fabrication of carbon nanotubes electronic devices on a CMOS chips. This research utilizes several kinds of techniques to reach purposes, such as, low temperature fabrication, manipulate technique (dielectrophoresis force), localized techniques, and surface modification by self-assembled monolayer (SAM), and moreover, to investigate the standard electrical transport characteristics of these CNTFETs. In the experimental process, the SWCNTs-based electronic devices microstructures are fabricated by standard CMOS process and wet etching process (post-process). Finally, CNTs are deposited and aligned CNTs on the predefined electrode pairs by using alternating current dielectrophoresis (AC-DEP) or photo resist defined adherent region for CNTs to complete the fabrication of SWCNTs-based electronic devices fabrication. These SWCNTs-based electronic devices are successfully fabricated and characteristics of the devices possess both weak gate modulation and no gate modulation, respectively. The former shows a turn-on current of 2nA and a conducting current ration of 2-5 folds, which is similar to the conventional silicon-based p-channel MOSFETs, while the latter is similar to characteristics of resistors. After utilizing the electroless plating to replace the low work function of TiN electrodes (~3.74eV) with the high work function of Ni/Au electrodes (~5.1eV), the formation of an improved metal-CNT contact and the reduced probabilities of surface oxidation help improve the performance of the CNT devices and promote the current of more than 10 times. Finally, the ideal of novel chemical and bio sensors, which relies on the CNTFETs technology combined with CMOS circuitry can be made on a single chip in the future.

並列關鍵字

Carbon nanotubes (CNTs) ； Carbon nanotubes Field-Effect Transistors (CNTFETs) ； Dielectrophoresis (DEP) ； Self-Assembled Monolayer (SAM) ； Complementary Metal-Oxide-Semiconductor (CMOS)

參考文獻

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