Browsing by Author "Chang, Chia-Yuan"

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A Hydrolyzed Chicken Extract CMI-168 Enhances Learning and Memory in Middle-Aged Mice
(2019-01-01)
Tsai, Sheng-Feng
;
Chang, Chia-Yuan
;
Yong, Shan-May
;
Lim, Ai-Lin
;
Nakao, Yoshihiro
There has been increasing evidence that consumption of dietary supplements or specific nutrients can influence cognitive processes and emotions. A proprietary chicken meat extraction, Chicken Meat Ingredient-168 (CMI-168), has previously been shown to enhance cognitive function in humans. However, the mechanism underlying the CMI-168-induced benefits remains unclear. In this study, we investigated the effects of CMI-168 on hippocampal neuroplasticity and memory function in middle-aged (9-12 months old) mice. The mice in the test group (termed the "CMI-168 group") were fed dietary pellets produced by mixing CMI-168 and normal laboratory mouse chow to provide a daily CMI-168 dose of 150 mg/kg of body weight for 6 weeks. The control mice (termed the "Chow group") were fed normal laboratory mouse chow pellets. CMI-168 supplementation did not affect the body weight gain, food intake, or exploratory behavior of the mice. In the novel object recognition test, the CMI-168 group showed better hippocampus-related non-spatial memory compared to the control Chow group. However, spatial memory examined by the Morris Water Maze test was similar between the two groups. There was also no significant difference in the induction and maintenance of long-term potentiation and dendritic complexity of the hippocampal cornu ammonis region 1 (CA1) neurons, as well as the levels of neuroplasticity-related proteins in the hippocampi of the CMI-168 and Chow groups. Interestingly, we observed that CMI-168 appeared to protect the mice against stress-induced weight loss. In conclusion, dietary supplementation of CMI-168 was found to improve learning and memory in middle-aged mice, independent of structural or functional changes in the hippocampus. The resilience to stress afforded by CMI-168 warrants further investigation.
Accurate Performance Evaluation of HEMT Devices for High-Speed Logic Applications through Rigorous Device Modelling Technique
(2007)
Hsu, Heng-Tung
;
Chang, Chia-Yuan
;
Hsu, Heng-Shou
;
Chang, Edward Yi
;
材料科學與工程學系
Tremendous progress has been made recently in the research of novel nanotechnology for future nano-electronic applications. Among all the possible technologies, III-V FETs particularly the heterostructure High Electron Mobility Transistors (HEMT) have demonstrated promising results to be the future device technology for high-speed logic applications. Precise evaluation of the delay performance for HEMT requires highly accurate intrinsic device models extracted from available measurements. In this paper, a rigorous device modelling technique based on 3-D full wave electromagnetic analysis of the device structure is presented. This technique is efficient and accurate, and the determined equivalent circuit model fits the measured S-parameter very well within the frequency range of interest.
AlGaAs/InGaAs high electron mobility transistor grown on Si substrate with Ge/Ge(x)Si(1-x) metamorphic buffer layers
(2008-09-01)
Chang, Edward Yi
;
Huang, Jui-Chien
;
Lin, Yueh-Chin
;
Hsieh, Yen-Chang
;
Chang, Chia-Yuan
Al(0.12)Ga(0.88)As/In(0.18)Ga(0.82)As high-electron-mobility transistor (HEMT) growth oil a Si substrate using the Ge/Ge(x)Si(1-x) buffer is demonstrated. This is the first demonstration of Al(0.12)Ga(0.88)As/In(0.18)Ga(0.82)As HEMT growth on a Ge/Ge(x)Si(1-x) metamorphic buffer layer. The electron mobility ill tile In(0.18)Ga(0.82)As channel of the HEMT sample was 3.550cm(2)/(Vs). After fabrication. the HEMT device demonstrated a saturation current of 150mA/mm with a transconductance 01 155mS/ inns. The wel behaved characteristics of the HEMT device oil the Si substrate are believed to be due to the very thin buffer layer achieved and the lack of tile antiphase boundary (APB) formation and Ge diffusion into the GaAs layers.
AlGaAs/InGaAs high electron mobility transistor grown on Si substrate with Ge/GexSi1-x metamorphic buffer layers
(2008-09-01)
Chang, Edward Yi
;
Huang, Jui-Chien
;
Lin, Yueh-Chin
;
Hsieh, Yen-Chang
;
Chang, Chia-Yuan
Al0.12Ga0.88As/In0.18Ga0.82As high-electron-mobility transistor (HEMT) growth oil a Si substrate using the Ge/GexSi1-x buffer is demonstrated. This is the first demonstration of Al0.12Ga0.88As/In0.18Ga0.82As HEMT growth on a Ge/GexSi1-x metamorphic buffer layer. The electron mobility ill tile In0.18Ga0.82As channel of the HEMT sample was 3.550cm(2)/(Vs). After fabrication. the HEMT device demonstrated a saturation current of 150mA/mm with a transconductance 01 155mS/ inns. The wel behaved characteristics of the HEMT device oil the Si substrate are believed to be due to the very thin buffer layer achieved and the lack of tile antiphase boundary (APB) formation and Ge diffusion into the GaAs layers.
An AlGaAs/InGaAs HEMT Grown on Si Substrate with Ge/GexSi1-x Metamorphic Buffer Layers
(2008)
Chang, Edward Yi
;
Lin, Yueh-Chin
;
Hsiao, Yu-Lin
;
Hsieh, Y. C.
;
Chang, Chia-Yuan
An AlGaAs/InGaAs HEMT grown on Si substrate with Ge/GexSi1-x buffer is demonstrated. The Ge/GexSi1-x metamorphic buffer layer used in this structure was only 1.0 mu m thick. The electron mobility in the In0.18Ga0.82As channel of the HEMT sample was 3,550 cm(2)/Vs. After fabrication, the HEMT device demonstrated a saturation current of 150 mA/mm and a maximum transconductance of 155 mS/mm. The well behaved characteristics of the HEMT device on the Si substrate are believed to be due to the very thin buffer layer achieved and the lack of the antiphase boundaries (APBs) formation and Ge diffusion into the GaAs layers. Index Terms: HEW GaAs on Si, SiGe buffer layer
Coherent phonon manipulation in coupled mechanical resonators
(2013-08-01)
Okamoto, Hajime
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Gourgout, Adrien
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Chang, Chia-Yuan
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Onomitsu, Koji
;
Mahboob, Imran
Coupled nanomechanical resonators have recently attracted great attention for both practical applications and fundamental studies owing to their sensitive sympathetic oscillation dynamics(1-10). A challenge to the further development of this architecture is the coherent manipulation of the coupled oscillations. Here, we demonstrate strong dynamic coupling between two GaAs-based mechanical resonators by periodically modulating (pumping) the stress using a piezoelectric transducer. This strong coupling enables coherent transfer of phonon populations between the resonators, namely phonon Rabi oscillations(11-13). The nature of the dynamic coupling can also be tuned from a linear first-order interaction to a nonlinear higher-order process in which more than one pump phonon mediates the coherent oscillations (that is, multi-pump phonon mixing). This coherent manipulation is not only useful for controlling classical oscillations(14) but can also be extended to the quantum regime(11-13), opening up the prospect of entangling two distinct macroscopic mechanical objects(15,16).
Coherent phonon manipulation in coupled mechanical resonators
(2013-08-01)
Okamoto, Hajime
;
Gourgout, Adrien
;
Chang, Chia-Yuan
;
Onomitsu, Koji
;
Mahboob, Imran
Coupled nanomechanical resonators have recently attracted great attention for both practical applications and fundamental studies owing to their sensitive sympathetic oscillation dynamics(1-10). A challenge to the further development of this architecture is the coherent manipulation of the coupled oscillations. Here, we demonstrate strong dynamic coupling between two GaAs-based mechanical resonators by periodically modulating (pumping) the stress using a piezoelectric transducer. This strong coupling enables coherent transfer of phonon populations between the resonators, namely phonon Rabi oscillations(11-13). The nature of the dynamic coupling can also be tuned from a linear first-order interaction to a nonlinear higher-order process in which more than one pump phonon mediates the coherent oscillations (that is, multi-pump phonon mixing). This coherent manipulation is not only useful for controlling classical oscillations(14) but can also be extended to the quantum regime(11-13), opening up the prospect of entangling two distinct macroscopic mechanical objects(15,16).
Coherent phonon manipulation in coupled mechanical resonators (vol 9, pg 480, 2013)
(2013-09-01)
Okamoto, Hajime
;
Gourgout, Adrien
;
Chang, Chia-Yuan
;
Onomitsu, Koji
;
Mahboob, Imran
Coherent phonon manipulation in coupled mechanical resonators (vol 9, pg 480, 2013)
(2013-09-01)
Okamoto, Hajime
;
Gourgout, Adrien
;
Chang, Chia-Yuan
;
Onomitsu, Koji
;
Mahboob, Imran
Effects of Wet Chemical and Trimethyl Aluminum Treatments on the Interface Properties in Atomic Layer Deposition of Al(2)O(3) on InAs
(2010-11-01)
Trinh, Hai-Dang
;
Chang, Edward Yi
;
Wong, Yuen-Yee
;
Yu, Chih-Chieh
;
Chang, Chia-Yuan
The reduction of native oxides on an In As surface using various wet and dry chemical treatments including hydrochloric acid (HCl) treatment sulfide treatment and in situ trimethyl aluminum (TMA) treatment before the atomic layer deposition (ALD) of Al(2)O(3) on In As is studied X ray photoelectron spectrum (XPS) results show that the effect of surface cleaning by TMA was apparent almost after the first pulse but that TMA cleaning is not as effective as wet chemical surface cleaning The combination of wet chemical treatment and TMA pretreatment is the most effective method for In As surface cleaning as indicated by the XPS analysis Capacitance-voltage (C-V) and current density-voltage (J-V) characteristics on metal-oxide-semiconductor capacitance (MOSCAP) structures were also investigated to evaluate the Al(2)O(3)/n In As interface quality after different surface treatments and the results are consistent with the XPS analysis (C) 2010 The Japan Society of Applied Physics
Effects of Wet Chemical and Trimethyl Aluminum Treatments on the Interface Properties in Atomic Layer Deposition of Al2O3 on InAs
(2010-11-01)
Trinh, Hai-Dang
;
Chang, Edward Yi
;
Wong, Yuen-Yee
;
Yu, Chih-Chieh
;
Chang, Chia-Yuan
The reduction of native oxides on an In As surface using various wet and dry chemical treatments including hydrochloric acid (HCl) treatment sulfide treatment and in situ trimethyl aluminum (TMA) treatment before the atomic layer deposition (ALD) of Al2O3 on In As is studied X ray photoelectron spectrum (XPS) results show that the effect of surface cleaning by TMA was apparent almost after the first pulse but that TMA cleaning is not as effective as wet chemical surface cleaning The combination of wet chemical treatment and TMA pretreatment is the most effective method for In As surface cleaning as indicated by the XPS analysis Capacitance-voltage (C-V) and current density-voltage (J-V) characteristics on metal-oxide-semiconductor capacitance (MOSCAP) structures were also investigated to evaluate the Al2O3/n In As interface quality after different surface treatments and the results are consistent with the XPS analysis (C) 2010 The Japan Society of Applied Physics
Evaluation of RF and logic performance for 80 nm InAs/InGaAs composite channel HEMTs using gate sinking technology
(2007)
Kuo, Chien-I
;
Hsu, Heng-Tung
;
Chang, Chia-Yuan
;
Chang, Edward Yi
;
Hsu, Heng-Shou
80-nm-gate In(0.7)Ga(0.3)As/InAs/In(0.7)Ga(0.3)As composite channel high-electron mobility transistors (HEMTs) fabricated using platinum (Pt) buried gate as the Schottky contact metal were evaluated for RF and logic application. After gate sinking at the 250 degrees C for 3 minutes, the device exhibited a high g. value of 1590mS/mm at V(d) = 0.5V and the current gain cutoff frequency f(T) was measured to be 494 GHz. The intrinsic gate delay time was calculated to be 0.78 psee at supply voltage of 0.6 V. This is the highest f(T) achieved for 80 nm gate length HEMT devices. These superior performances are attributed to the reduction of distance between. gate and channel, and the reduction of parasitic gate capacitances during gate-sinking process.
Fabrication of 0.15-mu m Gamma-shaped gate In0.52Al0.48As/In0.6Ga0.4As metamorphic HEMTs using DUV lithography and tilt dry-etching technique
(2007-02-01)
Lien, Yi-Chung
;
Chen, Szu-Hung
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Chang, Edward Yi
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Lee, Ching-Ting
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Chu, Li-Hsin
An In0.52Al0.48As/In0.6Ga0.4As metamorphic high-electron mobility transistor (MHEMT) with 0.15-mu m Gamma-shaped gate using deep ultraviolet lithography and tilt dry-etching technique is demonstrated. The developed submicrometer gate technology is simple and of low cost as compared to the conventional E-beam lithography or other hybrid techniques. The gate length is controllable by adjusting the tilt angle during the dry-et ching process. The fabricated 0.15-mu m In0.52Al0.48As/In0.6Ga0.4As MHEMT using this novel technique shows a saturated drain-source current of 680 mA/mm and a transconductance of 728 mS/mm. The f(T) and f(max) of the MHEMT are 130 and 180 GHz, respectively. The developed technique is a promising low-cost alternative to the conventional submicrometer E-beam gate technology used for the fabrication for GaAs MHEMTs and monolithic microwave integrated circuits.
Fast and improved bioimaging via temporal focusing multiphoton excitation microscopy with binary digital-micromirror-device holography
(2018-11-01)
Sie, Yong Da
;
Chang, Chia-Yuan
;
Lin, Chun-Yu
;
Chang, Nan-Shan
;
Campagnola, Paul J.
Conventional temporal focusing-based multiphoton excitation microscopy (TFMPEM) can offer wide-field optical sectioning with an axial excitation confinement of a few microns. To improve the axial confinement of TFMPEM, a binary computer-generated Fourier hologram (CGFH) via a digital-micromirror-device (DMD) was implemented to intrinsically improve the axial confinement by filling the back-focal aperture of the objective lens. Experimental results show that the excitation focal volume can be condensed and the axial confinement improved about 24% according to the DMD holography. In addition, pseudouniform MPE can be achieved using two complementary CGFHs with rapid pulse-width modulation switching via the DMD. Furthermore, bioimaging of CV-1 in origin with SV40 genes-7 cells demonstrates that the TFMPEM with binary DMD holography can improve image quality by enhancing axial excitation confinement and rejecting out-of-focus excitation. (C) 2018 Society of Photo-Optical Instrumentation Engineers (SPIE)
Graphene oxide dot-based microstructures via dispersion and support of bovine serum albumin
(2016-10-01)
Chang, Hsin-Yu
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Lin, Chun-Yu
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Chang, Chia-Yuan
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Teng, Hsisheng
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Campagnola, Paul J.
Three-dimensional graphene oxide-based microstructures have great potential for use in microelectronic and biomedical applications and can be fabricated by using two-photon excitation photochemical processes. In such excitation processes, rose Bengal is the preferred candidate as the photoactivator in two-photon crosslinking; nevertheless, it induces graphene oxide self-aggregation. Herein, bovine serum albumin (BSA) is adopted to prevent graphene oxide dot (GOD) aggregation even at very high GOD fabrication-solution concentrations, yet still supports GOD microstructures. In this manner, three-dimensional freeform GOD microstructures with different GOD concentrations were developed. Furthermore, the biocomparability of the GOD microstructure with the help of added biomaterials such as BSA was verified under living cell incubation. (C) 2016 Optical Society of America
Graphene quantum dots conjugated with polymers for two-photon properties under two-photon excitation
(2016)
Kuo, Wen-Shuo
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Hsu, Chih-Li Lilian
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Chen, Hua-Han
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Chang, Chia-Yuan
;
Kao, Hui-Fang
Few studies have investigated the two-photon properties of graphene quantum dots (GQDs) and GQD-conjugated polymers. The results of the present study revealed that conjugated polymers containing nitrogen and sulfur atoms caused higher quantum confinement of emissive energy to be trapped on the surface of nanomaterials, resulting in a high-photoluminescence quantum yield and notable two-photon properties. Additionally, the nanomaterials generated no reactive oxygen species-dependent oxidative stress on cells and served as promising two-photon contrast probes.
High Perfonnance InAs-Channel HEMT for Low Voltage Milimeter Waive Applications
(2007)
Hsu, Heng-Tung
;
Chang, Chia-Yuan
;
Chang, Edward Yi
;
Ku, Chien-, I
;
Miyamoto, Yasuyuki
An 80-nm InP HEMT with InAs channel and InGaAs sub-channels has been fabricated. The high current gain cutoff frequency (ft) of 350 GHz and maximum oscillation frequency (fmax) of 360 GRz were obtained at VDS = 0.7 V due to the high electron mobility in the InAs channel. DC and RF characterizations on the device have been performed and the on-sate breakdown voltage of the device was measured to be 1.75V. A 2-stage MMIC gain block was designed using such device. A simulated gain of better than 12 dB from 54 GHz to 71 GRz with only 14mW DC power consumption was achieved. Such high performance HEMTs demonstrated in this study shows great potential for very low power millimeter wave applications.
High-performance In0.52Al0.48As/In(0.6)Ga(0.)4As power metamorphic HEMT for Ka-band applications
(2006)
Chang, Chia-Yuan
;
Chang, Edward Yi
;
Lien, Yi-Chung
;
Miyamoto, Yasuyuki
;
Chen, Szu-Hung
A 70-nm In0.52Al0.48As/In0.6Ga0.4As power MHEMT with double delta-doping was fabricated and evaluated. The device has a high transconductance of 827 mS/mm. The saturated drain-source current of the device is 890 mA/mm. A current gain cutoff frequency (f(T)) of 200 GHz and a maximum oscillation frequency of 300 GHz were achieved due to the nanometer gate length and the high Indium content in the channel. When measured at 32 GHz, the 4 x 40 mu m device demonstrates a maximum output power of 14.5 dBm with P1dB of 11.1 dBm and the power gain is 9.5 dB. The excellent DC and RF performance of the 70-nm MHEMT shows a great potential for Ka-band power applications.
High-performance In0.52Al0.48As/In0.6Ga0.4As power metamorphic high electron mobility transistor for Ka-band applications
(2007-06-01)
Chang, Chia-Yuan
;
Chang, Edward Yi
;
Lien, Yi-Chung
;
Miyamoto, Yasuyuki
;
Kuo, Chien-I
A 70nm In0.52Al0.48As/In0.6Ga0.4As power metamorphic high electron mobility transistor (MHEMT) with a double delta-doping structure was fabricated and evaluated. The device has a high transconductance of 827mS/mm. The saturated drain-source current of the device is 890mA/mm. A current gain cutoff frequency (f(T)) of 200GHz and a maximum oscillation frequency (f(max)) of 300GHz were achieved owing to the nanometer gate length and high indium content in the channel. When measured at 32 GHz, the 0.07x160 mu m(2) device demonstrates a maximum output power of 14.5dBm (176mW/mm) and a P I dB of 11.1dBm (80mW/mm) with a 9.5dB power gain. The excellent DC and RF performance of the 70mn MHEMT are comparable to those of InP-based HEMTs and show the great potential for Ka-band power applications.
Improved and fast biotissue imaging by temporal focusing widefield multiphoton microscopy with spatially modulated illumination
(2019-01-01)
Chang, Chia-Yuan
;
Lin, Chun-Yu
;
Hovhannisyan, Vladimir A.
;
Chen, Shean-Jen
;
光電學院
A developed temporal focusing-based multiphoton microscope (TFMPM) has a digital micromirror device (DMD) which is adopted not only as a blazed grating for light spatial dispersion but also for patterned illumination simultaneously. Herein, the TFMPM has been extended to implement spatially modulated illumination at structured frequency and orientation to increase the beam coverage at the back-focal aperture of the objective lens. The axial excitation confinement (AEC) of TFMPM can be condensed from 3.0 mu m to 1.5 mu m for a 50% improvement. Furthermore, a multiline scanning mechanism based on the DMD can push its AEC nearly equivalent to line scanning-based TFMPM to 1.5 mu m from optimal 3.0 mu m of the conventional TFMPM. By using the TFMPM with structured illumination and multiline scanning, reconstructed biotissue images according to the condensed AEC structured illumination are shown obviously superior in contrast and better scattering suppression.