Device study, chemical doping, and logic circuits based on transferred aligned single-walled carbon nanotubes

Department of Electrical Engineering, University of Southern California, Los Angeles, California 90089, USA
Applied Physics Letters (Impact Factor: 3.3). 08/2008; 93(3):033101 - 033101-3. DOI: 10.1063/1.2956677
Source: IEEE Xplore


In this paper, high-performance back-gated carbon nanotube field-effect transistors based on transferred aligned carbon nanotubes were fabricated and studies found that the on/off ratio can reach 107 and the current density can reach 1.6 μ A /μ m after electrical breakdown. In addition, chemical doping with hydrazine was used to convert the p -type aligned nanotube devices into n -type. These devices were further utilized to demonstrate various logic circuits, including p -type metal-oxide-semiconductor inverters, diode-loaded inverters, complementary metal-oxide-semiconductor inverters, NAND, and NOR gates. This approach could work as the platform for future nanotube-based nanoelectronics.

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Available from: H.-S. Philip Wong
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    • "Nevertheless, the high temperature needed for good quality CNT growth is incompatible with current CMOS technologies [10]. Alternatively , various methods for CNT assembly in the post-synthetic regime have been developed [11] [12] [13] [14] [15] [16]. Among then, acdielectrophoresis (DEP) using an ac electric field to integrate CNTs onto pre-patterned electrodes has proven its potential [17]. "
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    • "Hence, chemical doping of nanotubes provides an efficient way to control the electrical properties of CNTFETs. It has been reported that p-type CNTFETs can be converted to n-type via potassium doping [4], by functional groups existing in polymers and molecules [5] [3] [6]. Modulation of nanotube device performance while maintaining its p-type behavior, however, is very important for electronic applications. "
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    • "In the past few years, carbon nanotubes (CNTs) have been extensively investigated due to their remarkable structures and excellent properties [1]. They have also been identified as potential materials for a broad range of useful devices [2,3], especially in the area of field emission devices [4-7]. CNT arrays always have attracted considerable attentions as ideal electron emitters for their excellent field emission properties [5-7]. "
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