Browsing by Author "Lu, Ming-Wei"

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An Implantable 128-Channel Wireless Neural-Sensing Microsystem using TSV-Embedded Dissolvable mu-Needle Array and Flexible Interposer
(2017-01-01)
Huang, Po-Tsang
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Huang, Yu-Chieh
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Wu, Shang-Lin
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Hu, Yu-Chen
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Lu, Ming-Wei
For implanted neural-sensing devices, one of the remaining challenges is to transmit stable power/data (P/D) transmission for high spatiotemporal resolution neural data. This paper presents a miniaturized implantable 128-channel wireless neural-sensing microsystem using TSV-embedded dissolvable mu-needle array, a flexible interposer and 4 dies by 2.5D/3D TSV heterogeneous SiP technology. The 4 dies are 2 neural-signal acquisition ICs implemented by 90nm CMOS, 1 neural-signal processor by 40nm CMOS and 1 wireless P/D transmission circuitry by 0.18 mu m CMOS. Thus, the proposed wireless microsystem realizes 128-channel neural-signal sensing within the area of 5mm x 5mm, neural feature extraction and wireless P/D transmission using an on-interposer inductor. The overall average power of the circuits in this microsystem is only 9.85mW.
Interfacial reactions between Ti and Y2O3/Ca4Ti3O10 composites
(1970-01-01)
Lu, Ming-Wei
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Lin, Kun-Lin
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Lin, Chien-Cheng
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材料科學與工程學系
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Department of Materials Science and Engineering
In titanium casting, the interfacial reactions between selected Y2O3/Ca4Ti3O10 composites in contact with titanium at 1600 degrees C for 30 minutes in an argon environment were characterized using X-ray diffraction, scanning electron microscopy, and analytical transmission electron microscopy. Before contact with titanium, reaction phases of the Y2O3/Ca4Ti3O10 composites formed through hot pressing at 1500 degrees C or annealing at 1600 degrees C. These phases were identified as Ca4Ti3O10, Y2O3, and minor amounts of CaO. The amount of Ca4Ti3O10 in the composites gradually decreased as the amount of Y2O3 increased. When the Y2O3/Ca4Ti3O10 composites were in contact with titanium, a reaction layer of alpha-Ti and Y2O3 was formed near the interface of the composite side. Large amounts of calcium and oxygen were expelled toward the composite side from Ca4Ti3O10 near the interface to form CaO, which precipitated in the Ca4Ti3O10 and Y2O3 phases. Furthermore, no reaction phases were detected in titanium. Ca4Ti3O10 and Y2O3 can function as diffusion barrier layers to effectively suppress the diffusion of oxygen into titanium.
Investigation of the interactions between titanium and calcium zirconium oxide (CaZrO3) ceramics modified with alumina
(2019-01-01)
Lu, Ming-Wei
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Lin, Kun-Lin
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Lin, Chien-Cheng
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材料科學與工程學系
;
Department of Materials Science and Engineering
Powdered mixtures of CaO, ZrO2 and Al2O3 in various ratios were hot pressed. The mixtures reacted with titanium at 1600 degrees C for 30 min in argon to evaluate the suitable ceramic crucibles for casting of titanium. The interfacial microstructures between titanium and ceramic composites were characterized using X-ray diffractometer, scanning and transmission electron microscope. The produced hot pressed mixtures that were chemically bonded together, contained calcium aluminate (CaAl2O4), calcium dialuminate (CaAl4O7), cubic zirconia (c-ZrO2), and calcium zirconium oxide (CaZrO3). The increase in Al2O3 amount led to the decrease in CaZrO3 amount and an increase in the amount of CaAl2O4, CaAl4O7 and c-ZrO2 due to the reaction of CaO and Al2O3. At the end of the reaction of the ceramic mixtures with Ti at 1600 degrees C for 30 min, the acicular alpha-Ti and beta'-Ti were formed at the interface of Ti and the composites containing up to 10 vol.% Al O-2(3). In composites containing more than 20 vol.% Al2O3, Ti3Al5 was found at the interface instead of alpha-Ti and beta'-Ti. Furthermore, CaZrO3, ZrO2 and Ca3Al2O6 existed on the sides of the ceramic far away from the interface. CaZrO3/Al2O3 composites with less than 20 vol.% Al2O3 could be a potential crucible or mould material for productive applications in titanium casting.