The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform

Chee Yee Kwok - One of the best experts on this subject based on the ideXlab platform.

  • aluminum induced crystallization of in situ phosphorus doped e beam evaporated silicon films for high Gauge Factor piezo resistors
    IEEE Electron Device Letters, 2018
    Co-Authors: Ian Chuang, Aron Michael, Anastasia Soeriyadi, Chee Yee Kwok
    Abstract:

    A polysilicon film with high Gauge Factor formed at a low thermal budget of 450 °C is reported in this paper. The polysilicon was formed using in-situ phosphorus doped ultra-high vacuum e-beam evaporated amorphous silicon film as a precursor for aluminum induced crystallization (AIC). The crystallization, electrical and piezo-resistive properties of the resulting films for various phosphorus doping levels have been studied. The results show that the Gauge Factor of the AIC polysilicon film increases with phosphorous doping level of the precursor. The reduction in doping concentration and formation of large grains with average size of $8.77~\mu \text{m}$ have allowed a Gauge Factor of 77 to be at obtained with phosphorus doping of $2\times 10^{19}$ cm−3 in the precursor. This, to our knowledge, is the highest Gauge Factor reported for polysilicon and may lead to post-CMOS monolithic integration of high performance strain sensors.

  • in situ phosphorus doped ultra high vacuum e beam evaporated silicon for high Gauge Factor polysilicon
    International Conference on Micro Electro Mechanical Systems, 2018
    Co-Authors: Ian Chuang, Aron Michael, Anastasia Soeriyadi, Chee Yee Kwok
    Abstract:

    This paper reports a low temperature, high Gauge Factor polysilicon piezo-resistor fabricated by aluminium induced crystallization (AIC) process at 450oC. Through in-situ phosphorus doping of ultra-high vacuum e-beam evaporated amorphous silicon precursor, the Gauge Factor of the AIC polysilicon is increased from 38 to 56. This is a significant increase in its sensitivity, and the highest reported Gauge Factor under CMOS-MEMS compatible temperature range.

  • high Gauge Factor piezoresistors using aluminium induced crystallisation of silicon at low thermal budget
    2017
    Co-Authors: Ian Chuang, Aron Michael, Chee Yee Kwok
    Abstract:

    This paper reports on polysilicon piezo-resistors that are fabricated at a low thermal budget using aluminium-induced-crystallization (AIC) of ultra-high-vacuum e-beam evaporated silicon films. By in-situ phosphorus doping of precursor amorphous silicon films e-beam evaporated at room temperature on aluminium layer, we are able to increase and control the Gauge Factor of the polysilicon films formed by AIC at 450 °C. Piezo-resistors made from the polysilicon films are integrated on microcantilever beams to measure their Gauge Factors. Gauge Factors as high as 62 is obtained for 2 × 1018/cm3 phosphorus doping level in the precursor amorphous silicon film. The measured Gauge Factors are significantly higher than previously reported values for polysilicon films.

Scott E Thompson - One of the best experts on this subject based on the ideXlab platform.

  • simulation of algan gan high electron mobility transistor Gauge Factor based on two dimensional electron gas density and electron mobility
    Journal of Applied Physics, 2010
    Co-Authors: Andrew D Koehler, Amit Gupta, Toshikazu Nishida, Scott E Thompson
    Abstract:

    The Gauge Factor of AlGaN/GaN high-electron-mobility transistor was determined theoretically, considering the effect of stress on the two-dimensional electron gas (2DEG) sheet carrier density and electron mobility. Differences in the spontaneous and piezoelectric polarization between the AlGaN and GaN layers, with and without external mechanical stress, were investigated to calculate the stress-altered 2DEG density. Strain was incorporated into a sp3d5–sp3 empirical tight-binding model to obtain the change in electron effective masses under biaxial and uniaxial stress. The simulated longitudinal Gauge Factor (−7.9±5.2) is consistent with experimental results (−2.4±0.5) obtained from measurements eliminating parasitic charge trapping effects through continuous subbandgap optical excitation.

  • Simulation of AlGaN/GaN high-electron-mobility transistor Gauge Factor based on two-dimensional electron gas density and electron mobility
    Journal of Applied Physics, 2010
    Co-Authors: Andrew D Koehler, Amit Gupta, Toshikazu Nishida, Scott E Thompson
    Abstract:

    The Gauge Factor of AlGaN/GaN high-electron-mobility transistor was determined theoretically, considering the effect of stress on the two-dimensional electron gas (2DEG) sheet carrier density and electron mobility. Differences in the spontaneous and piezoelectric polarization between the AlGaN and GaN layers, with and without external mechanical stress, were investigated to calculate the stress-altered 2DEG density. Strain was incorporated into a sp3d5–sp3 empirical tight-binding model to obtain the change in electron effective masses under biaxial and uniaxial stress. The simulated longitudinal Gauge Factor (−7.9±5.2) is consistent with experimental results (−2.4±0.5) obtained from measurements eliminating parasitic charge trapping effects through continuous subbandgap optical excitation.

Ian Chuang - One of the best experts on this subject based on the ideXlab platform.

  • aluminum induced crystallization of in situ phosphorus doped e beam evaporated silicon films for high Gauge Factor piezo resistors
    IEEE Electron Device Letters, 2018
    Co-Authors: Ian Chuang, Aron Michael, Anastasia Soeriyadi, Chee Yee Kwok
    Abstract:

    A polysilicon film with high Gauge Factor formed at a low thermal budget of 450 °C is reported in this paper. The polysilicon was formed using in-situ phosphorus doped ultra-high vacuum e-beam evaporated amorphous silicon film as a precursor for aluminum induced crystallization (AIC). The crystallization, electrical and piezo-resistive properties of the resulting films for various phosphorus doping levels have been studied. The results show that the Gauge Factor of the AIC polysilicon film increases with phosphorous doping level of the precursor. The reduction in doping concentration and formation of large grains with average size of $8.77~\mu \text{m}$ have allowed a Gauge Factor of 77 to be at obtained with phosphorus doping of $2\times 10^{19}$ cm−3 in the precursor. This, to our knowledge, is the highest Gauge Factor reported for polysilicon and may lead to post-CMOS monolithic integration of high performance strain sensors.

  • in situ phosphorus doped ultra high vacuum e beam evaporated silicon for high Gauge Factor polysilicon
    International Conference on Micro Electro Mechanical Systems, 2018
    Co-Authors: Ian Chuang, Aron Michael, Anastasia Soeriyadi, Chee Yee Kwok
    Abstract:

    This paper reports a low temperature, high Gauge Factor polysilicon piezo-resistor fabricated by aluminium induced crystallization (AIC) process at 450oC. Through in-situ phosphorus doping of ultra-high vacuum e-beam evaporated amorphous silicon precursor, the Gauge Factor of the AIC polysilicon is increased from 38 to 56. This is a significant increase in its sensitivity, and the highest reported Gauge Factor under CMOS-MEMS compatible temperature range.

  • high Gauge Factor piezoresistors using aluminium induced crystallisation of silicon at low thermal budget
    2017
    Co-Authors: Ian Chuang, Aron Michael, Chee Yee Kwok
    Abstract:

    This paper reports on polysilicon piezo-resistors that are fabricated at a low thermal budget using aluminium-induced-crystallization (AIC) of ultra-high-vacuum e-beam evaporated silicon films. By in-situ phosphorus doping of precursor amorphous silicon films e-beam evaporated at room temperature on aluminium layer, we are able to increase and control the Gauge Factor of the polysilicon films formed by AIC at 450 °C. Piezo-resistors made from the polysilicon films are integrated on microcantilever beams to measure their Gauge Factors. Gauge Factors as high as 62 is obtained for 2 × 1018/cm3 phosphorus doping level in the precursor amorphous silicon film. The measured Gauge Factors are significantly higher than previously reported values for polysilicon films.

G Bruni - One of the best experts on this subject based on the ideXlab platform.

  • evaluation of the Gauge Factor for membranes assembled by single walled carbon nanotubes
    Applied Physics Letters, 2004
    Co-Authors: A Reale, P Regoliosi, L Tocca, Paolo Lugli, Silvia Orlanducci, M L Terranova, G Bruni
    Abstract:

    Samples of single-walled carbon nanotubes (SWCNTs) organized in the form of thin membranes have been investigated in order to correlate the mechanical deformation and conductivity behavior of such nanosized material. The nanotubes Gauge Factor of piezoresistivity has been evaluated by comparing the electrical responses induced by the deformation in SWCNT membranes and in Si substrates with the same electrical characteristics. The Gauge Factor of the SWCNT–Si systems was found to be a Factor 2.3–2.5 larger than that of the Si substrates. We have also observed that temperature slightly enhances the piezoresistive response of the SWCNT.

Masaya Toda - One of the best experts on this subject based on the ideXlab platform.

  • vanadium doped molybdenum disulfide film based strain sensors with high Gauge Factor
    Applied Physics Express, 2019
    Co-Authors: Jinhua Li, Naoki Inomata, Masaya Toda
    Abstract:

    This paper reports the piezoresistive performance of the two-dimensional (2D) material of vanadium (V)-doped molybdenum disulfide (MoS2) films based on sulfurization of sputtered Mo thin films. I–V characteristics indicate that V atom doping indeed decreases the resistivity of MoS2. Strain sensors based on V-doped MoS2 resistive elements were fabricated. By using a four-point bending method, a Gauge Factor (GF) of 140 under compressive and tensile strain conditions was obtained. The piezoresistive effect of V-doped MoS2 with different V sputtering conditions was also investigated. The doping method introducing V atoms as dopants is found to play an important role in enhancing piezoresistive performance.

  • high Gauge Factor strain sensors based on vanadium doped molybedenum disulfide 2d films
    International Conference on Micro Electro Mechanical Systems, 2019
    Co-Authors: Naoki Inomata, Masaya Toda
    Abstract:

    This paper reports the piezoresistive performance of two-dimensional (2D) material of vanadium (V) doped MoS 2 films. A novel method for forming large-area and uniform 2D film is based on sulfurization of a Mo thin film. I-V characteristics indicate that V atoms doping indeed decreases the resistivity of MoS 2 . Strain sensors based on V-doped MoS 2 resistive elements are fabricated. By using a four-point bending method, a Gauge Factor (GF) of ~140 for V-doped MoS 2 is obtained. This demonstration of substitutional doping in MoS 2 could help in realizing high sensitive strain sensing applications.