Browsing by Author "Hsu, Shun-Chieh"

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A ZnO/InN/GaN Heterojunction Photodetector with Extended Infrared Response
(2015)
Hsu, Lung-Hsing
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Hsu, Shun-Chieh
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Lee, Hsin-Ying
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Tsai, Yu-Lin
;
Lin, Da-Wei
An extended infrared photoresponse is observed in a ZnO/InN/GaN heterojunction diode with InN grown by MOCVD. The external quantum efficiency is measured between 1200 and 1800 nm and can be as high as 3.55%.
All Inorganic Perovskite Quantum Dots Hybrid Green Light-Emitting Diode with Stable Performance
(2018-01-01)
Yu, Chung-Ping
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Chung, Meng-Ting
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Chen, Tzu-Yu
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Huang, Yu-Ming
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Huang, Chung-Ping
A silica-coated inorganic perovskite quantum dot hybrid light-emitting diodes is aged continuously in high and low light intensity conditions. Both blue and ultra-violet-pumped samples showed stable performances up to 104 hours.
An Investigation on 25Gb/s Ultra-Short Cavity Quantum Well Lasers Operated at Elevated Temperatures
(2019-01-01)
Tsai, Yi-Lin
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Chen, Bo-Hong
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Hsu, Shun-Chieh
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Shih, Hsiang-Yun
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Lu, Po-Yen
A Fabry-Perot quantum well laser with ultra-short cavity is designed and fabricated. The emission wavelength is at 1310nm band which is important for data center applications. The shortest cavity length is 25 mu m, and the laser has mW-class output with low threshold currents (4mA in average). At room temperature, an opened eye diagram with 28Gb/s transmission rate can be observed. Clear 25Gb/s eye patterns from 15 degrees C to 65 degrees C are also demonstrated.
An Investigation on Stable and Continuous Operation of Hybrid Perovskite Quantum Dot Light Emitting Diodes
(2019-01-01)
Cho, Yu-Yun
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Hsu, Shun-Chieh
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Huang, Yu-Ming
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Shih, Hsiang-Yun
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Lee, Ting-Yu
Two different package structures of hybrid perovskite quantum dots light emitting diodes were demonstrated with stable and continuous light emission. With boron nitride nanoparticles, the lifetime of device is expected to be thousands of hours.
Colloidal Quantum Dot Enhanced Dual-Junction Tandem Solar Cells
(2016-01-01)
Hsu, Shun-Chieh
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Kao, Yu-Cheng
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Han, Hau-Vei
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Kuo, Hao-Chung
;
Horng, Ray-Hua
In this work, we demonstrate the the enhancement of two type hybrid QD dual-junction solar cell. The green QD520 sample, shows better performance than blue QD450 sample in current density and power conversion efficiency. The enhancement of short-circuit current and power conversion efficiency for green QD450 sample are 4.43% and 3.77% and the blue QD520 samples are 9.44% and 5.78%. For short wavelength, the enhancement can mainly be attributed to the photon downshift effect and antireflection, for long wavelength, it only the antireflection effect.
Compact Photonic Integrated Chip for Tunable Microwave Generation
(2014-03-01)
Chien, Chen-Yu
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Lo, Yen-Hua
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Wu, Yu-Chang
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Hsu, Shun-Chieh
;
Tseng, Hung-Ruei
A tunable microwave generation is demonstrated by monolithically integrated photonic chip, which combines a mirror section and two distributed feedback (DFB) lasers. The focus ion beam technology was employed to achieve high-quality air/semiconductor slab for the mirror. Two DFB lasers (named slave and master lasers, respectively) can operate in a single fundamental mode when they are individually pumped. A microwave signal with the differential frequency between the two lasers can be obtained through optical heterodyning. A tunable microwave signal up to 25.5 GHz can be generated by adjusting the injected currents of the two DFB lasers. A four-wave mixing spectrum was measured and the linewidth of the generated radio frequency signal is 1.9 MHz.
Evaluation of Luminescent Downshifting Effect of Perovskite Quantum Dots on Semiconductor Solar Cells
(2018-01-01)
Chen, Chun-Hong
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Yu, Chung-Ping
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Huang, Yu-Ming
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Chan, Yueh-Lin
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Huang, Chung-Ping
The luminescent down-shifting effect of the perovskite quantum dots on single junction GaAs solar cells are examined and discussed. The perovskite quantum dots can provide an effective way to convert ultra-violet photons in solar spectrum to visible ones which can be transformed into electron-hole pairs more efficiently. Three different designs are tried: direct-dispense, ITO nano-whisker up and ITO nano-whisker down. In this experiment, we use perovskite quantum dots(QDs) with the concentration of 1mg/ml and emit photons of the wavelength 530nm (CsPbBr3), and the various volume of perovskite QDs were deposited on the solar cell to observe the possible luminescent down-shifting phenomenon.
Fabrication of a Highly Stable White Light-Emitting Diode With Multiple-Layer Colloidal Quantum Dots
(2017-09-01)
Hsu, Shun-Chieh
;
Ke, Li-Ann
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Lin, Hsiu-Ching
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Chen, Teng-Ming
;
Lin, Huang-Yu
A hybrid design by combination of colloidal quantum dots and a traditional light-emitting diode is demonstrated to realize a high-quality white source. The cadmium telluride quantum dots are wrapped in the sodium chloride ionic crystal to prevent from environmental corrosion. Three different colors (red, yellow, and green) are picked to provide a better color rendering capability. The single color layer sequence in the package can be properly designed to obtain the best spectrum output. A stable (over 1500 h of continuous operation) and high color rendering index (> 92) quantum dot white light-emitting diode can be demonstrated.
Feasibility Study for Double Luminescent Down-shifting Effect in A Dual Junction Solar Cell
(2019-01-01)
Huang, Yu-Ming
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Cho, Yu-Yun
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Hsu, Shun-Chieh
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Kao, Sheng-Feng
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Shih, Hsiang-Yun
In this work, we discuss the feasibility of two color photons for boosting up the short-circuit current and power conversion efficiency in tandem solar cell. One of them is by luminescent down-shifting (LDS) effect, and the other one is the infrared light emitting diode at 820nm. The CdZnSeS/ZnS quantum dots are used in this study. It can convert ultra-violet photons to visible ones which could be efficiently transformed into electron-hole pairs. The infrared-radiation LED can increase photo-generated carriers of the bottom GaAs solar cell. Finally, short-circuit current would significantly increase from 10.46 mA/cm(2) to 13.81 mA/cm(2), and power conversion efficiency increase from 19.89 to 25.22%. This result shows the possible double-LDS effect for solar cell enhancement in the future.
High performance ultraviolet micro-LED arrays for fine-pitch micro displays
(2019-01-01)
Tsai, Yi-Lin
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Huang, Yu-Ming
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Yang, Shu-Mei
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Kuo, Wei-Hung
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Fang, Yen-Hsiang
Highly efficient ultraviolet micro LED arrays are demonstrated. Small devices (5 microns in size) suitable for high resolution (725 ppi) can be produced with low leakage current and good emission spectra stability. A 10 by 10 array is achieved with passive-matrix driving connection.
Highly Efficient Hybrid Quantum Dot Light Emitting Diodes with Prolonged Lifetime
(2015)
Hsu, Shun-Chieh
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Chen, Yin-Han
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Tu, Zong-Yi
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Han, Hau-Vei
;
Lin, Shih-Li
A highly efficient LED is demonstrated by incorporating the colloidal quantum dots and sodium chloride. Further lifetest shows great stability up to 104 hours under 194 mW/cm(2) of UV pump power.
Highly Efficient Hybrid Quantum Dot White Light Emitting Diodes with Prolonged Lifetime
(2016)
Hsu, Shun-Chieh
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Jheng, Yun-Han
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Han, Hau-Vei
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Kuo, Hao-Chung
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Lin, Chien-Chung
A white LED is demonstrated by incorporating three kinds of colloidal quantum dots and sodium chloride. Further lifetest shows great stability up to 146 hours under 203.4 mW/cm(2) of blue pump power.
Highly Stable and Efficient Hybrid Quantum Dot Light-Emitting Diodes
(2015-10-01)
Hsu, Shun-Chieh
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Chen, Yin-Han
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Tu, Zong-Yi
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Han, Hau-Vei
;
Lin, Shih-Li
A highly efficient and reliable hybrid quantum dot (QD) light-emitting diode (LED) is demonstrated and analyzed. The CdTe colloidal QDs are embedded in the sodium chloride (NaCI) ionic crystal to prevent external wear. The GaN-based ultraviolet (UV) LED is used as the excitation source. The mixture of colloidal QD/NaCI composite and polymer can be filled inside the standard LED package and optically pumped by the UV LED. Two different filling layer designs are fabricated simultaneously for comparative study. Due to extra scattering brought by the sodium chloride grains, the resultant photon conversion efficiency (POE) can be as high as 72.6% at the medium current level. For the long-term stability assessment, two different UV pumping intensities were set up: One is equivalent to 111 mW/cm(2), and the other is 906 mW/cm(2). With this encapsulation, the stability of the colloidal QD light output over time can be improved, and a prolonged lifetime of 6488 h can be demonstrated under the continuous UV aging condition.
InN-based heterojunction photodetector with extended infrared response
(2015-11-30)
Hsu, Lung-Hsing
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Kuo, Chien-Ting
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Huang, Jhih-Kai
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Hsu, Shun-Chieh
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Lee, Hsin-Ying
The combination of ZnO, InN, and GaN epitaxial layers is explored to provide long wavelength photodetection capability in the GaN based materials. Growth temperature optimization was performed to obtain the best quality of InN epitaxial layer in the MOCVD system. The temperature dependent photoluminescence (PL) can provide the information about thermal quenching in the InN PL transitions and at least two non-radiative processes can be observed. X-ray diffraction and energy dispersive spectroscopy are applied to confirm the inclusion of indium and the formation of InN layer. The band alignment of such system shows a typical double heterojunction, which is preferred in optoelectronic device operation. The photodetector manufactured by this ZnO/GaN/InN layer can exhibit extended long-wavelength quantum efficiency, as high as 3.55%, and very strong photocurrent response under solar simulator illumination. (C) 2015 Optical Society of America
Microwave behavior of a monolithic dual-wavelength DFB laser based on current model
(2020-09-15)
Huang, Chung-Ping
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Huang, Yu-Ming
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Hwang, Yi-Chia
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Dong, Yao-Zhong
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Hsu, Shun-Chieh
A driving current based model describing the optical heterodyne output of a monolithic dual-wavelength DFB laser is established. The linear relationship between the driving current and the laser output wavelength was applied to obtain the simple equation for this purpose. Actual measured data from the real devices were used for the initial parameter extraction and the practical model can then be built. By using this model, the influence of different laser parameters towards the radio frequency signal generation and different current configuration on the output characteristic can be demonstrated. This can facilitate the future design of such integrated photonic devices.
Microwave Spectral Characteristics of the Three-Section Distributed Feedback Lasers
(2018-01-01)
Chen, Chun-Hong
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Hsiao, Fu-Chun
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Dong, Yao-Zhong
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Chan, Yueh-Lin
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Chen, Yi-Hsun
The three-section DFB lasers are used for RF signal generation. With an extra section, it can lime the RF peak frequency farther than the two-section one, and can also simultaneously generate two single-mode RF signals.
Modeling of Current Dependent Microwave Behavior of a Two-Section DFB Laser
(2015)
Hwang, Yi-Chia
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Dong, Yao-Zhong
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Hsu, Shun-Chieh
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Lin, Chien-Chung
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光電系統研究所
A current dependent model of RF generation is developed for the dual wavelength lasers. Because of the nature of current based operation, it is more convenient to have current as the main variable. From the numerical analysis, certain parameters such as wavelength change rate and linewidth enhancement factor (LEF) can affect the generated RF power more substantially than other parameters.
Multiple-Layered Type-II GaSb/GaAs Quantum Ring Solar Cells Under Concentrated Solar Illumination
(2016-01-01)
Jheng, Yun-Han
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Hsu, Shun-Chieh
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Wu, Shou-Hung
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Sheu, Jinn-Kong
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Lo, Yuan-Ting
A multiple-layered type-II quantum ring nanostructure was embedded in the regular GaAs single junction solar cell to extend its infrared response. Three different designs were implemented and the location of quantum ring layers was investigated. Under one Sun condition, the n-type quantum ring device showed higher J(sc) than the GaAs reference while the reduction of V-oc is minimum among all these quantum ring samples. Further tests through the filtered infrared light demonstrate the enhanced photo-currents from quantum ring devices. An increase as high as 292% in reverse-biased photo-current can be observed.
Numerical Analysis of Nano-scale Solar Cells with Surface States
(2015)
Lin, Chien-chung
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Lin, Shih-Li
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Tseng, Hung-Ruei
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Hsu, Shun-Chieh
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Chen, Yin-Han
As the scale of the solar cell moves into nanometer regime, the numerical analysis should evolve at the same pace. By using the Matlab (R) as the tool and solving the general Poisson and continuity equations, we are able to have a good platform for the nano-scale solar cells. By adapting proper parameters, the perovskite solar cells and their behavior under different surface recombination conditions were analyzed.
Numerical Evaluation on the Nano-rod Array on a N-side-up Thin-film GaAs Solar Cells
(2017-01-01)
Lin, Yan-Zhang
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Hsu, Shun-Chieh
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Wu, Po-Ching
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Hsu, Chia-Jhe
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Lin, Chien-Chung
In this work, we demonstrate the influence of the substrate thickness and the arrangement of nano-rod arrays on the n-side up GaAs thin film solar cell. The J-V characteristics can be altered significantly with different design parameters. The thickness of the substrate can have strong influence on the collected carrier. Also the closeness of the rod to each other can affect the short-circuit current as well due to the limited penetration depth of the photons.