The Experts below are selected from a list of 368220 Experts worldwide ranked by ideXlab platform
Mitsue Ogawa - One of the best experts on this subject based on the ideXlab platform.
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High-Temperature Stability in yttria-stabilized zirconia
Heat Transfer Research, 2008Co-Authors: Mitsue OgawaAbstract:Yttria-stabilized zirconia has been studied as a candidate standard reference material for the determination of thermal properties. This study evaluated the high-Temperature Stability, which is important for yttria-stabilized zirconia to be used for a standard reference material, using a common material of fine ceramics, Referceram ZR1 (zirconia). The high-Temperature Stability was evaluated by measuring the change in the thermal diffusivity before and after heat treatment at Temperatures between 200 °C and 1500 °C. No change in the thermal diffusivity was observed when the samples were treated at Temperatures equal to or below 900 °C. However, it was revealed that the changes in the thermal diffusivity were caused by the transformation and separation of the crystal phase and the cracks that occur at grain boundaries when the samples were treated at Temperatures equal to or above 1000 °C. From these results, we confirmed that Referceram ZR1 is sufficiently stable for use as a reference material at Temperatures equal to or below 900 °C. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(2): 57–67, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20193
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High‐Temperature Stability in yttria‐stabilized zirconia
Heat Transfer—Asian Research, 2008Co-Authors: Mitsue OgawaAbstract:Yttria-stabilized zirconia has been studied as a candidate standard reference material for the determination of thermal properties. This study evaluated the high-Temperature Stability, which is important for yttria-stabilized zirconia to be used for a standard reference material, using a common material of fine ceramics, Referceram ZR1 (zirconia). The high-Temperature Stability was evaluated by measuring the change in the thermal diffusivity before and after heat treatment at Temperatures between 200 °C and 1500 °C. No change in the thermal diffusivity was observed when the samples were treated at Temperatures equal to or below 900 °C. However, it was revealed that the changes in the thermal diffusivity were caused by the transformation and separation of the crystal phase and the cracks that occur at grain boundaries when the samples were treated at Temperatures equal to or above 1000 °C. From these results, we confirmed that Referceram ZR1 is sufficiently stable for use as a reference material at Temperatures equal to or below 900 °C. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(2): 57–67, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20193
Xixiang Zhang - One of the best experts on this subject based on the ideXlab platform.
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A new concept to enhance piezoelectricity and Temperature Stability in KNN ceramics
Chemical Engineering Journal, 2020Co-Authors: Xixiang ZhangAbstract:Abstract To relieve the sensitivity of piezoelectric coefficient (d33) to composition and strengthen Temperature Stability of strain in potassium sodium niobate {(K, Na)NbO3, KNN} ceramics, we proposed a new concept, tuning the trade-off between long-range ordering (LRO) and polar nanoregions (PNRs), and realized it by tailoring the content of bismuth (Bi) in an already-constructed multiphase coexistence, namely, 0.96(K0.48Na0.52)(Nb0.955Sb0.045)O3-0.04(BixNa4-3x)0.5ZrO3-0.3 mol%Fe2O3 ceramics. We obtained not only the high retention of > 83% at x = 0.80–1.10 in d33 but also higher d33 at x = 0.90–0.95, relieving the sensitivity of d33 to composition. We also obtained not only the enhanced strain but also the high retention of ≥ 79% over a wide Temperature range of 20–180 °C at x = 1.10, irrespective of the electric field, strengthening the Temperature Stability. We demonstrated that high d33 values hinge on the trade-off between LRO and PNRs, and the enhanced Temperature Stability of strain originates from the diffused multiphase coexistence and the reduced contribution of domain switching. Therefore, the new concept helps further design high-performance KNN-based ceramics for practical application.
Mona Zaghloul - One of the best experts on this subject based on the ideXlab platform.
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Temperature Stability Analysis of CMOS-SAW Devices by Embedded Heater Design
IEEE Transactions on Device and Materials Reliability, 2008Co-Authors: Onur Tigli, Mona ZaghloulAbstract:The design, finite element (FE) modeling, and electrical characterization of an embedded heater in complementary metal-oxide-semiconductor (CMOS) are presented. The heater is used to analyze the Temperature Stability behavior of CMOS-surface acoustic wave (SAW) devices. The heater employs n-well layer of standard CMOS technology to provide high efficiency resistive heating without physically perturbing the SAW architectures and performances. A detailed 3-D model and FE investigation is laid out to characterize the heat, current, Temperature, and thermal energy distributions within the substrate and the piezoelectric material of interest ZnO. Electrical characterization based on Wheatstone configuration is presented to analyze the Temperature Stability of the sputtered ZnO and the CMOS-SAW delay lines. A Temperature coefficient of frequency of -48.815/degC for the fabricated SAW devices with operating frequency of 322.5 MHz is obtained. The experimental results show close agreement with the FE simulations. The results demonstrate that the embedded heater design can be used as a robust analytical tool to investigate Temperature Stability of CMOS-SAW devices and potentially be utilized as an on-chip element for chemical, biological, and Temperature sensor applications.
Kuang Sheng - One of the best experts on this subject based on the ideXlab platform.
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High Temperature Stability evaluation of SiC MOSFETs
2014 IEEE 26th International Symposium on Power Semiconductor Devices & IC's (ISPSD), 2014Co-Authors: Weicheng Zhou, Xueqian Zhong, Kuang ShengAbstract:SiC MOSFETs are expected to have higher thermal runaway Temperature, compared with other SiC power devices. In this paper, high Temperature Stability of SiC MOSFETs is investigated by experiments and simulations. At room Temperature, the maximum steady-state junction Temperature of the SiC MOSFET is measured to exceed 270°C and saber simulations based on experimental model reproduce the thermal process.
Onur Tigli - One of the best experts on this subject based on the ideXlab platform.
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Temperature Stability Analysis of CMOS-SAW Devices by Embedded Heater Design
IEEE Transactions on Device and Materials Reliability, 2008Co-Authors: Onur Tigli, Mona ZaghloulAbstract:The design, finite element (FE) modeling, and electrical characterization of an embedded heater in complementary metal-oxide-semiconductor (CMOS) are presented. The heater is used to analyze the Temperature Stability behavior of CMOS-surface acoustic wave (SAW) devices. The heater employs n-well layer of standard CMOS technology to provide high efficiency resistive heating without physically perturbing the SAW architectures and performances. A detailed 3-D model and FE investigation is laid out to characterize the heat, current, Temperature, and thermal energy distributions within the substrate and the piezoelectric material of interest ZnO. Electrical characterization based on Wheatstone configuration is presented to analyze the Temperature Stability of the sputtered ZnO and the CMOS-SAW delay lines. A Temperature coefficient of frequency of -48.815/degC for the fabricated SAW devices with operating frequency of 322.5 MHz is obtained. The experimental results show close agreement with the FE simulations. The results demonstrate that the embedded heater design can be used as a robust analytical tool to investigate Temperature Stability of CMOS-SAW devices and potentially be utilized as an on-chip element for chemical, biological, and Temperature sensor applications.
