• Transactions on Electrical and Electronic Materials
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• v.9 no.4
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• pp.169-172
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• 2008

We attempted to fabricate carbon nanotube field effect transistor (CNT-FET) using single walled carbon nanotube(SWNT) on the heavily doped Si substrate used as a bottom gate, source and drain electrode were fabricated bye-beam lithography on the 500 nm thick $SiO_2$ gate dielectric layer. We investigated electrical and physical properties of this CNT-FET using Scanning Probe Microscope(SPM) and conventional method based on tungsten probe tip technique. The gate length of CNT-FET was 600 nm and the diameter of identified SWNT was about 4 nm. We could observed gating effect and typical p-MOS property from the obtained $V_G-I_{DS}$ curve. The threshold voltage of CNT-FET is about -4.6V and transconductance is 47 nS. In the physical aspect, we could identified SWNT with phase mode of SPM which detecting phase shift by force gradient between cantilever tip and sample surface.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.1
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• pp.88-92
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• 2010

Bottom gate and top gate field-effect transistor based carbon nanotube(CNT) were fabricated by CMOS process. Carbon nanotube directly grown by thermal chemical vapor deposition(CVD) using Ethylene ($C_2H_4$) gas at $700^{\circ}C$. The growth properties of CNTs on the device were analyzed by SEM and AFM. The electrical transport characteristics of CNT FET were investigated by I-V measurement. Transport through the nanotubes is dominated by holes at room temperature. By varying the gate voltage, bottom gate and top gate field-effect transistor successfully modulated the conductance of FET device.

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1035-1038
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• 2013

Rolling circle amplification (RCA) of DNA on an aligned-carbon nanotube (a-CNT) surface was electrically interfaced by the a-CNT based filed effect transistor (FET). Since the electric conductance of the a-CNT will be dependent upon its local electric environment, the electric conductance of the FET is expected to give a very distinctive signature of the surface reaction along with this isothermal DNA amplification of the RCA. The a-CNT was initially grown on the quartz wafer with the patterned catalyst by chemical vapor deposition and transferred onto a flexible substrate after the formation of electrodes. After immobilization of a primer DNA, the rolling circle amplification was induced on chip with the a-CNT based FET device. The electric conductance showed a quite rapid increase at the early stage of the surface reaction and then the rate of increase was attenuated to reach a saturated stage of conductance change. It took about an hour to get the conductance saturation from the start of the conductance change. Atomic force microscopy was used as a complementary tool to support the successful amplification of DNA on the device surface. We hope that our results contribute to the efforts in the realization of a reliable nanodevice-based measurement of biologically or clinically important molecules.

• Journal of Sensor Science and Technology
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• v.18 no.2
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• pp.168-172
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• 2009

In this paper, we present the carbon nanotube field-effect transistor(CNT-FET) with a double-gate structure. A Carbon nanotube film was aligned by the Langmuir-Blodgett technique and $SiN_x$ was deposited to protect from water, oxygen, and other contaminants. We measured the electrical characteristics of the proposed device as the function of the $V_{BG}$, $V_{TG}$. From this result, we can confirm that proposed device might be employed as a biosensor.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.5
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• pp.389-393
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• 2007

We fabricated field-effect transistor based carbon nanotubes(CNTs) directly grown by thermal chemical vapor deposition(CVD) and analyzed their performance. The Ethylene ($C_2H_4$), hydrogen($H_2$) and Argon(Ar) gases were used for the growth of CNTs at $700\;^{\circ}C$. The growth properties of CNTs on the device were analyzed by SEM and AFM. The electrical transport characteristics of CNT FET were investigated by I-V measurement. Transport through the nanotubes is dominated by holes at room temperature. By varying the gate voltage, we successfully modulated the conductance of FET device by more than 7 orders of magnitude.

• Proceeding of EDISON Challenge
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• 2015.03a
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• pp.350-353
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• 2015

최근 에너지 효율과 소형화측면에서 한계를 보이는 Metal-Oxide-Semiconductor Field-Effect Transistor(MOSFET)을 대체할 수 있는 소자로 Tunneling FET(TFET)이 주목받고 있다. 본 논문에서는 탄소나노튜브(Carbon Nanotube, CNT) TFET을 시뮬레이션하여 전자회로의 기본 단위인 인버터(Inverter)를 설계한다. 설계한 인버터의 성능을 CNT-MOSFET 인버터와 비교하여 저전력 디지털 회로로써의 가능성을 확인한다.

• Proceeding of EDISON Challenge
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• 2013.04a
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• pp.246-249
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• 2013

EDISON 나노물리 사이트에 탑재된 탄소나노튜브 FET 소자 시뮬레이션 툴을 이용하여 나노 CNT 소자에서의 p-n접합이 갖는 특성을 살펴보았다. 순방향 바이어스에서는 일반적인 p-n접합과 유사한 특성을 보이나 그 원리는 다름을 알 수 있었으며, 역방향 바이어스에서는 밴드 대 밴드 터널링에 의한 전류가 발생함을 확인하였다. 또한 이러한 역방향 바이어스 하의 전류가 도핑농도에 따라 변함을 확인하여 실제 CNT 소자의 도핑농도를 예측해볼 수 있는 가능성을 확인하였다.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.179.2-179.2
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• 2014

Carbon nanotubes (CNT)-metal contacts play an important role in nanoelectronics applications such as field-effect transistor (FET) devices. Using Al and (10,0) CNT, we have recently showed that the CNT-metal contacts mediated via topological defects within CNT exhibits intrinsically low contact resistance, thanks to the preservation of the sp2 bonding network at the metal-CNT contacts.[1] It is well-established that metals with good wetting property such as Pd consistently yield good contacts to both metallic and semiconducting CNTs. In this work, the electronic and charge transport properties of the interfaces between capped CNT and Pd will be investigated based on first-principles computations and compared with previous results obtained for the Al electrodes.

• International Journal of Precision Engineering and Manufacturing
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• v.7 no.1
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• pp.42-46
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• 2006

This paper presents a method for deposition an individual carbon nanotube (CNT). The alignment of a single CNT is very useful to perform studies related to applications in FET (Field Emitted Transistor), SET (Single Electron Transistor) and to make chemical sensor as well as bio sensors. In this study, we developed the deposition method of a CNT individualized in a solution. Using the electrokinetic method, we found the optimum conditions to assemble the nanotube and discussed about plausible explanation for the assembling mechanism. These results will be available to use for making the CNT sensor device.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.1169-1173
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• 2015

This paper presents vertical carbon nanotube (CNT) field effect transistors (FETs). For the first time, the author successfully fabricated vertical CNT-based FETs on an anodized aluminum oxide (AAO) template by using atomic layer deposition (ALD). Single walled CNTs were vertically grown and aligned with the vertical pores of an AAO template. By using ALD, a gate oxide material (Al₂O₃) and a gate metal (Au) were centrally located inside each pore, allowing the vertical CNTs grown in the pores to be individually gated. Characterizations of the gated/vertical CNTs were carried and the successful gate integration with the CNTs was confirmed.