Lee Jungchul, Liao Albert, Pop Eric, King William P
Department of Mechanical Science and Engineering, Micro and Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Nano Lett. 2009 Apr;9(4):1356-61. doi: 10.1021/nl803024p.
We utilize a multifunctional atomic force microscope (AFM) cantilever applying highly localized temperature and electric fields to interrogate transport in single-wall carbon nanotube field-effect transistors (CNTFETs). The probe can be operated either in contact with the CNT, in intermittent contact, or as a Kelvin probe, and can independently control the electric field, mechanical force, and temperature applied to the CNT. We modulate current flow in the CNT with tip-applied electric field, and find this field-effect depends upon both cantilever heating and CNT self-heating. CNT transport is also investigated with AFM tip temperature up to 1170 degrees C. Tip-CNT thermal resistance is estimated at 1.6 x 10(7) K/W and decreases with increasing temperature. Threshold force (<100 nN) for reliable contact mode imaging is extracted and used to determine set points for nanotube manipulation, such as displacement or cutting. The ability to measure thermal coupling to a single-molecule electronic device could offer new insights into nanoelectronic devices.
我们使用一种多功能原子力显微镜(AFM)悬臂,通过施加高度局部化的温度和电场来研究单壁碳纳米管场效应晶体管(CNTFET)中的输运情况。该探针可以与碳纳米管接触操作、间歇接触操作或作为开尔文探针操作,并且能够独立控制施加到碳纳米管上的电场、机械力和温度。我们通过施加在探针尖端的电场来调制碳纳米管中的电流,发现这种场效应取决于悬臂加热和碳纳米管自身加热。还利用高达1170摄氏度的AFM探针温度对碳纳米管输运进行了研究。估计探针 - 碳纳米管的热阻为1.6×10⁷K/W,并且随着温度升高而降低。提取了可靠接触模式成像的阈值力(<100 nN),并将其用于确定纳米管操作(如位移或切割)的设定点。测量与单分子电子器件的热耦合能力可为纳米电子器件提供新的见解。