Browsing by Author "Chen, Yi-Ru"

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Energy-Efficient HfAlOx NCFET: Using Gate Strain and Defect Passivation to Realize Nearly Hysteresis-Free Sub-25mV/dec Switch with Ultralow Leakage
(2017-01-01)
Fan, Chia-Chi
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Cheng, Chun-Hu
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Chen, Yi-Ru
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Liu, Chien
;
Chang, Chun-Yen
We experimentally demonstrated that ferroelectric HfAlOx negative capacitance FETs using gate strain and defect passivation can realize a nearly hysteresis-free forward/reverse swing of < 25 mV/dec for symmetric switch, a wide sub-60 mV/dec SS range over 4 decade of I-DS to reach an ultralow I-off of 4 fA/mu m, and a very high I-on/I-off ratio of > 10(8). Under the influence of gate strain and negative capacitance, the NCFETs exhibits 66% I-on enhancement and 27% V-T reduction. In addition, the fluorine defect passivation reduces oxygen vacancies of gate stack to further mitigate interface depolarization field and help to significantly reinforce surface potential amplification effect during NC operation.
Examining the function of TPX2 during neurite morphogenesis
(2014-04-01)
Hwang, Eric
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Chen, Wen-Shin
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Chen, Yi-Ru
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Huang, Yung-An
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交大名義發表
Impact of Ferroelectric Domain Switching in Nonvolatile Charge-Trapping Memory
(2017-01-01)
Fan, Chia-Chi
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Chiu, Yu-Chien
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Liu, Chien
;
Liou, Guan-Lin
;
Lai, Wen-Wei
In this work, we proposal a ferroelectric domain to enhance program/erase/read efficiency of conventional charge-trapping nonvolatile memory. The ferroelectric-domain-dominated HfZrO/HfON memory shows the better subthreshold characteristics than control charge-trapping structure (HfO2/HfON). Additionally, the memory speed with ferroelectric polarization (similar to 800ns) is more than three orders of magnitude faster than that of control trapping type.
Manifestation of a Second Dirac Surface State and Bulk Bands in THz Radiation from Topological Insulators
(2015-09-15)
Tu, Chien-Ming
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Yeh, Tien-Tien
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Tzeng, Wen-Yen
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Chen, Yi-Ru
;
Chen, Hsueh-Ju
Topological insulators (TIs) are interesting quantum matters that have a narrow bandgap for bulk and a Dirac-cone-like conducting surface state (SS). The recent discovered second Dirac surface state (SS) and bulk bands (BBs) located similar to 1.5 eV above the first SS are important for optical coupling in TIs. Here, we report on the time-domain measurements of THz radiation generated from TIs n-type Cu0.02Bi2Se3 and p-type Bi2Te3 single crystals by ultrafast optical pulse excitation. The observed polarity-reversal of the THz pulse originated from transient current is unusual, and cannot be reconciled with the photo-Dember effect. The second SS and BBs are found to be indispensable for the explanation of the unusual phenomenon. Thanks to the existence of the second SS and BBs, TIs manifest an effective wide band gap in THz generation. The present study demonstrates that time-domain THz spectroscopy provide rich information of the optical coupling and the electronic structure of TIs.
Program/Erase Speed and Data Retention Trade-Off in Negative Capacitance Versatile Memory
(2017-01-01)
Fan, Chia-Chi
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Chiu, Yu-Chien
;
Liu, Chien
;
Liou, Guan-Lin
;
Lai, Wen-Wei
In this work, we investigated the performance tradeoff between program/erase speed and data retention of ferroelectric HfZrO memory. The monoclinic HfNO layer with a trapping mechanism was employed to improve the data retention. Under the thickness optimization of HfNO, the HfZrO/HfNO gate stack can be functionalized with volatile and non-volatile operation.
Recent Progress in White Light-Emitting Electrochemical Cells
(1970-01-01)
Su, Hai-Ching
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Chen, Yi-Ru
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Wong, Ken-Tsung
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照明與能源光電研究所
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Institute of Lighting and Energy Photonics
Solid-state white light-emitting electrochemical cells (LECs) exhibit the following advantages: simple device structures, low operation voltage, and compatibility with inert metal electrodes. LECs have been studied extensively since the first demonstration of white LECs in 1997, due to their potential application in solid-state lighting. This review provides an overview of recent developments in white LECs, specifically three major aspects thereof, namely, host-guest white LECs, nondoped white LECs, and device engineering of white LECs. Host-guest strategy is widely used in white LECs. Host materials are classified into ionic transition metal complexes, conjugated polymers, and small molecules. Nondoped white LECs are based on intra- or intermolecular interactions of emissive and multichromophore materials. New device engineering techniques, such as modifying carrier balance, color downconversion, optical filtering based on microcavity effect and localized surface plasmon resonance, light extraction enhancement, adjusting correlated color temperature of the output electroluminescence spectrum, tandem and/or hybrid devices combining LECs with organic light-emitting diodes, and quantum-dot light-emitting diodes improve the device performance of white LECs by ways other than material-oriented approaches. Considering the results of the reviewed studies, white LECs have a bright outlook.