• Proceedings of the Korean Vacuum Society Conference
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• 2005.02a
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• pp.130-130
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• 2005

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.2
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• pp.116-125
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• 2006

We have presented a nanoelectromechanical (NEM) model based on atomistic simulations. Our models were applied to a NEM device as called a nanotube random access memory (NRAM) operated by an atomistic capacitive model including a tunneling current model. We have performed both static and dynamic analyses of a NRAM device. The turn-on voltage obtained from molecular dynamics simulations was less than the half of the turn-on voltage obtained from the static simulation. Since the suspended carbon nanotube (CNT) oscillated with the amplitude for the oscillation center under an externally applied force, the quantity of the CNT-gold interaction in the static analysis was different from that in the dynamic analysis. When the gate bias was applied, the oscillation centers obtained from the static analysis were different from those obtained from the dynamics analysis. Therefore, for the range of the potential difference that the CNT-gold interaction effects in the static analysis were negligible, the vibrations of the CNT in the dynamics analysis significantly affected the CNT-gold interaction energy and the turn-on voltage. The turn-on voltage and the tunneling resistance obtained from our tunneling current model were in good agreement with previous experimental and theoretical works.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2005.09a
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• pp.27-30
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• 2005

A nanoelectromechanical (NEM) switching device based on carbon nanotube (CNT) was investigated using atomistic simulations. The model schematics for a CNT based three-terminal NEM switching device fabrication were presented. for the CNT-based three-terminal NEM switch, the interactions between the CNT-lever and the drain electrode or the substrate were very important. When the electrostatic force applied to the CNT-lever was the critical point, the CNT-lever was rapidly bent because of the attractive foroe between the CNT-lever and the drain. The energy curves for the pull-in and the pull-out processes showed the hysteresis loop that was induced by the adhesion of the CNT on the copper, which was the interatomic interaction between the CNT and the copper.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.361.1-361.1
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• 2016

Due to their high sensitivity, fast response, small energy consumption and ease of integration, nanoelectromechanical systems (NEMS) have attracted much interest in various applications such as high speed memory devices, energy harvesting devices, frequency tunable RF receivers, and ultra sensitive mass sensors. Since the device performance of NEMS is closely related with the mechanical and flexural properties of the material in NEMS, analysis of the mechanical and flexural properties such as intrinsic tensile stress and Young's modulus is a crucial factor for designing the NEMS structures. In the present work, the intrinsic mechanical properties of highly stressed silicon nitride (SiN) beams are investigated as a function of the beam length using two different techniques: (i) dynamic flexural measurement using optical interferometry and (ii) quasi-static flexural measurement using atomic force microscopy. The reliability of the results is analysed by comparing the results from the two different measurement techniques. In addition, the mass density, Young's modulus and internal stress of the SiN beams are estimated by combining the techniques, and the prospect of SiN based NEMS for application in high sensitive mass sensors is discussed.