The Experts below are selected from a list of 174 Experts worldwide ranked by ideXlab platform
Peidong Yang - One of the best experts on this subject based on the ideXlab platform.
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self transducing silicon nanowire electromechanical systems at room temperature
Nano Letters, 2008Co-Authors: X L Feng, M L Roukes, Peidong YangAbstract:Electronic readout of the motions of genuinely nanoscale mechanical devices at room temperature imposes an important challenge for the integration and application of nanoelectromechanical systems (NEMS). Here, we report the first experiments on piezoresistively transduced very high frequency Si nanowire (SiNW) resonators with on-chip electronic actuation at room temperature. We have demonstrated that, for very thin (∼90 nm down to ∼30 nm) SiNWs, their time-varying strain can be exploited for self-transducing the devices’ resonant motions at frequencies as high as ∼100 MHz. The strain of wire elongation, which is only second-order in doubly clamped structures, enables efficient displacement transducer because of the enhanced Piezoresistance Effect in these SiNWs. This intrinsically integrated transducer is uniquely suited for a class of very thin wires and beams where metallization and multilayer complex patterning on devices become impractical. The 30 nm thin SiNW NEMS offer exceptional mass sensitivities in the subzeptogram range. This demonstration makes it promising to advance toward NEMS sensors based on ultrathin and even molecular-scale SiNWs, and their monolithic integration with microelectronics on the same chip.
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Giant Piezoresistance Effect in silicon nanowires
Nature Nanotechnology, 2006Co-Authors: Rongrui He, Peidong YangAbstract:The Piezoresistance Effect of silicon^ 1 has been widely used in mechanical sensors^ 2 , 3 , 4 , and is now being actively explored in order to improve the performance of silicon transistors^ 5 , 6 . In fact, strain engineering is now considered to be one of the most promising strategies for developing high-performance sub-10-nm silicon devices^ 7 . Interesting electromechanical properties have been observed in carbon nanotubes^ 8 , 9 . In this paper we report that Si nanowires possess an unusually large Piezoresistance Effect compared with bulk. For example, the longitudinal Piezoresistance coefficient along the 〈111〉 direction increases with decreasing diameter for p-type Si nanowires, reaching as high as −3,550 × 10^−11 Pa^–1, in comparison with a bulk value of −94 × 10^−11 Pa^−1. Strain-induced carrier mobility change and surface modifications have been shown to have clear influence on Piezoresistance coefficients. This giant Piezoresistance Effect in Si nanowires may have significant implications in nanowire-based flexible electronics, as well as in nanoelectromechanical systems.
Jong Hyun Ahn - One of the best experts on this subject based on the ideXlab platform.
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Ultrafast terahertz spectroscopy of the inverse giant Piezoresistance Effect in silicon nanomembranes
CLEO: 2015, 2015Co-Authors: Jaeseok Kim, Houk Jang, Min-seok Kim, Jeong Ho Cho, Jong Hyun Ahn, Hyunyong ChoiAbstract:We observe the clear inverse Piezoresistance Effect in the silicon nanomembranes. Thickness-dependent optical-pump terahertz spectroscopy strongly corroborate that the Effect originates from the carrier-concentration changes via charge carrier trapping into strain-induced defect states.
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observation of the inverse giant Piezoresistance Effect in silicon nanomembranes probed by ultrafast terahertz spectroscopy
Nano Letters, 2014Co-Authors: Houk Jang, Hyunyong Choi, Jaeseok Kim, Min-seok Kim, Jeong Ho Cho, Jong Hyun AhnAbstract:The anomalous Piezoresistance (a-PZR) Effects, including giant PZR (GPZR) with large magnitude and inverse PZR of opposite, have exciting technological potentials for their integration into novel nanoelectromechanical systems. However, the nature of a-PZR Effect and the associated kinetics have not been clearly determined yet. Even further, there are intense research debates whether the a-PZR Effect actually exists or not; although numerous investigations have been conducted, the origin of the Effect has not been clearly understood. This paper shows the existence of a-PZR and provides direct experimental evidence through the performance of well-established electrical measurements and terahertz spectroscopy on silicon nanomembranes (Si NMs). The clear inverse PZR behavior was observed in the Si NMs when the thickness was less than 40 nm and the magnitude of the PZR response linearly increased with the decreasing thickness. Observations combined with electrical and optical measurements strongly corroborate ...
Yozo Kanda - One of the best experts on this subject based on the ideXlab platform.
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graphical representation and origin of Piezoresistance Effect in germanium
Journal of Physics: Conference Series, 2017Co-Authors: Kazunori Matsuda, Shiro Nagaoka, Yozo KandaAbstract:The longitudinal and transverse Piezoresistance coefficients of Ge at room temperature are represented graphically as a function of the crystal directions for orientation (001), (110) and (211) planes. Many valley model of conduction band and stress decoupling decoupling of the degenerate valence band into two bands of prolate and oblate ellipsoidal energy surface are shown to explain origin of the Piezoresistance. One this basis, comparison between Piezoresistance coefficient and theoretical model is discussed.
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Piezoresistance Effect of n type silicon temperature and concentration dependencies stress dependent Effective masses
PHYSICS OF SEMICONDUCTORS: 28th International Conference on the Physics of Semiconductors - ICPS 2006, 2007Co-Authors: Yozo Kanda, Kazunori MatsudaAbstract:N‐type Piezoresistance (PR) tensor component π44 is essentially independent of temperature and carrier concentration, but depends on them in higher impurity concentration (> 1020) since the Fermi level lowers due to the tail of the density‐of‐state (DOS). Although conduction Effective masses are affected by shear stress, which is the origin of π44, DOS Effective mass does not change. The dependencies and nonlinearity of the PR is discussed by taking the band‐tail.
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Piezoresistance Effect in p type silicon
PHYSICS OF SEMICONDUCTORS: 27th International Conference on the Physics of Semiconductors - ICPS-27, 2005Co-Authors: Yozo Kanda, Kazunori MatsudaAbstract:Difference between unstrained heavy and light hole Effective masses in the direction of applied strain obtained by D‐K‐K formula has correlated with the longitudinal Piezoresistance (PR) coefficient but not with the transverse PR. Graphical representation of the longitudinal PR coefficients calculated by macroscopic fourth rank PR tensor has proved the fact.
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Piezoresistance Effect of silicon
Sensors and Actuators A-physical, 1991Co-Authors: Yozo KandaAbstract:Abstract The principle of the Piezoresistance Effect (PR) of n- and p-Si is explained by the carrier-transfer mechanism and the Effective mass change. The origin of the shear Piezoresistance coefficient π 44 in n-Si is also a stress-induced Effective mass change. A graphical representation of the PR on crystallographic orientations and the Effect of impurity concentration on the PR are given for n- and p-Si. The non-linearity of the PR is also mentioned.
Houk Jang - One of the best experts on this subject based on the ideXlab platform.
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Ultrafast terahertz spectroscopy of the inverse giant Piezoresistance Effect in silicon nanomembranes
CLEO: 2015, 2015Co-Authors: Jaeseok Kim, Houk Jang, Min-seok Kim, Jeong Ho Cho, Jong Hyun Ahn, Hyunyong ChoiAbstract:We observe the clear inverse Piezoresistance Effect in the silicon nanomembranes. Thickness-dependent optical-pump terahertz spectroscopy strongly corroborate that the Effect originates from the carrier-concentration changes via charge carrier trapping into strain-induced defect states.
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observation of the inverse giant Piezoresistance Effect in silicon nanomembranes probed by ultrafast terahertz spectroscopy
Nano Letters, 2014Co-Authors: Houk Jang, Hyunyong Choi, Jaeseok Kim, Min-seok Kim, Jeong Ho Cho, Jong Hyun AhnAbstract:The anomalous Piezoresistance (a-PZR) Effects, including giant PZR (GPZR) with large magnitude and inverse PZR of opposite, have exciting technological potentials for their integration into novel nanoelectromechanical systems. However, the nature of a-PZR Effect and the associated kinetics have not been clearly determined yet. Even further, there are intense research debates whether the a-PZR Effect actually exists or not; although numerous investigations have been conducted, the origin of the Effect has not been clearly understood. This paper shows the existence of a-PZR and provides direct experimental evidence through the performance of well-established electrical measurements and terahertz spectroscopy on silicon nanomembranes (Si NMs). The clear inverse PZR behavior was observed in the Si NMs when the thickness was less than 40 nm and the magnitude of the PZR response linearly increased with the decreasing thickness. Observations combined with electrical and optical measurements strongly corroborate ...
Hyunyong Choi - One of the best experts on this subject based on the ideXlab platform.
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Ultrafast terahertz spectroscopy of the inverse giant Piezoresistance Effect in silicon nanomembranes
CLEO: 2015, 2015Co-Authors: Jaeseok Kim, Houk Jang, Min-seok Kim, Jeong Ho Cho, Jong Hyun Ahn, Hyunyong ChoiAbstract:We observe the clear inverse Piezoresistance Effect in the silicon nanomembranes. Thickness-dependent optical-pump terahertz spectroscopy strongly corroborate that the Effect originates from the carrier-concentration changes via charge carrier trapping into strain-induced defect states.
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observation of the inverse giant Piezoresistance Effect in silicon nanomembranes probed by ultrafast terahertz spectroscopy
Nano Letters, 2014Co-Authors: Houk Jang, Hyunyong Choi, Jaeseok Kim, Min-seok Kim, Jeong Ho Cho, Jong Hyun AhnAbstract:The anomalous Piezoresistance (a-PZR) Effects, including giant PZR (GPZR) with large magnitude and inverse PZR of opposite, have exciting technological potentials for their integration into novel nanoelectromechanical systems. However, the nature of a-PZR Effect and the associated kinetics have not been clearly determined yet. Even further, there are intense research debates whether the a-PZR Effect actually exists or not; although numerous investigations have been conducted, the origin of the Effect has not been clearly understood. This paper shows the existence of a-PZR and provides direct experimental evidence through the performance of well-established electrical measurements and terahertz spectroscopy on silicon nanomembranes (Si NMs). The clear inverse PZR behavior was observed in the Si NMs when the thickness was less than 40 nm and the magnitude of the PZR response linearly increased with the decreasing thickness. Observations combined with electrical and optical measurements strongly corroborate ...