學術出版;;Publications

Permanent URI for this communityhdl:11536/1

收集所有交通大學研究人員與學生個人或團體所發表之各項學術著作，涵蓋期刊論文、教師專書、學位論文等項。;;Collections of Publications of NCTU Researchers and Students Like Journal Papers and Thesis.

Browse

🏛️國立陽明交通大學機構典藏

Search Results

Now showing 1 - 10 of 12

Composite metal substrate for thin film AlGaInP LED applications
(2019-04-15)
Horng, R. H.
;
Sinha, Shreekant
;
Lee, C. P.
;
Feng, H. A.
;
Chung, C. Y.
The fabrication and feasibility assessment of n-side up, thin-epilayer, AlGaInPbased vertical light-emitting-diodes (LEDs; emitting area: 1 mm x 1 mm) with a copperinvar-copper-composite metal (CIC) substrate was obtained by wafer bonding and epilayer transferring technologies. The structure of CIC substrate is a top Cu layer of 20 mu m, a middle Invar layer of 64 mu m, and a bottom Cu layer of 20 mu m. The invar layer consists of Fe and Ni at a ratio of 70% to 30%. The coefficient of thermal expansion for CIC is about 6.1 x 10(-6) /K, which is similar to that of the GaAs substrate (5.7 x 10(-6)/K) and AlGaInP epilayers. Due to the high thermal conductivity (160 W/m-K) of 10(4)-mu m-thick CIC, the high performances of the packaged LEDs are obtained. They present a low red shift phenomenon (from 623 to 642 nm for 100 mA to 1 A) and a high output power 212 mW at 800 mA. The CIC substrate can be extended to fabricate high-efficiency thin film LEDs with conventional vertical electrodes. (c) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
Rolling up Ge microtube from bare-Ge substrate
(2014-08-15)
Chen, C. H.
;
Niu, H.
;
Huang, R. T.
;
Lee, C. P.
;
奈米科技中心
We show Ge microtubes can be rolled-up from bare-Ge wafer at almost any position, once these films are released from its substrate. (C) 2014 Elsevier B.V. All rights reserved.
Local structure and magnetic properties of ferromagnetic GaMnAs made by helium ion induced epitaxial crystallization annealing
(2014-08-15)
Chen, C. H.
;
Niu, H.
;
Yan, D. C.
;
Hsieh, H. H.
;
Huang, R. T.
In this study we show GaMnAs preparation by Mn implantation in GaAs followed by helium ion beam induced epitaxial crystallization annealing. The characteristics of the Mn-implanted layer were investigated by X-ray diffraction, and transmission electron microscopy. The magnetic nature of the Mn-implanted layer was investigated with a superconducting quantum interference device. Structure analysis showed that Mn ions were incorporated substitutionally into the GaAs lattice without the formation of any detectable secondary phases. The remanent magnetic moment exhibited room temperature ferromagnetism. Additional measurement using X-ray magnetic circular dichroism also revealed that the carriers were spin polarized. (C) 2014 Elsevier B.V. All rights reserved.
Compositional grading in GaAsSb grown on GaAs substrates
(2014-09-15)
Lin, Y. M.
;
Chen, C. H.
;
Wu, J. S.
;
Lee, C. P.
;
電子工程學系及電子研究所
The composition profile and lattice strain of GaAsSb grown on GaAs substrates by molecular beam epitaxy have been investigated using the Rutherford backscattering spectrometry (RBS) and X-ray reciprocal space mapping. Through RBS, we found that the Sb content in the layer increases from the interface to the top surface. The X-ray reciprocal space mapping shows that the GaAsSb lattice also gradually relaxes as the layer becomes thicker. The behavior of composition grading and gradual lattice relaxation is quite different from those of III-V ternary compounds with two group Ill atoms. (C) 2014 Elsevier B.V. All rights reserved.
2-3 mu m mid infrared light sources using InGaAs/GaAsSb "W" type quantum wells on InP substrates
(2010-11-15)
Pan, C. H.
;
Lin, S. D.
;
Lee, C. P.
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
We have investigated the InGaAs/GaAsSb/InAlGaAs/InAlAs type-II "W" quantum wells (QWs) grown on InP substrates by molecular beam epitaxy. The photoluminescence (PL) emission wavelength longer than 2.56 mu m at room temperature (RT) is demonstrated for the first time in this material system. The PL emission peaks of our designed samples can cover a wide range from 2 to 2.5 mu m at cryogenic temperature. The samples show good optical quality that the reduction in integrated PL intensity is only around one order of magnitude from 35 K to RT. We found that the integrated PL intensity decreased as the emission wavelength increased, which is due to the reduction in the electron-hole wave function overlap. This is consistent with the calculated result. In the power dependent PL measurements, the emission peak of "W" type QWs show blue shifts with the excitation power (P-ex) but does not follow the P-ex(1/3) rule as predicted by type-II band bending model. The localized states filling effect gives reasonable explanations for the observed phenomena. (C) 2010 American Institute of Physics. [doi:10.1063/1.3506427]
Novel chirped multilayer quantum-dot lasers
(2008-01-01)
Lin, G.
;
Chang, C. Y.
;
Tseng, W. C.
;
Lee, C. P.
;
Lin, K. F.
Chirped multilayer (N=10) QD lasers with 2-, 3- and 5-layer of longer-, medium-, and shorter-wavelength QD stacks, respectively, were grown in this work. Low threshold current density and high saturated modal gain were achieved in this specially designed QD structure. Empirical gain-current analysis was performed on this chirped multilayer QD structure for the first time. It was consistent with our spectral observations and provided valuable information on carrier recombination in chirped multilayer QD structure. Two novel spectral characteristics were discovered also for the first time. First, simultaneous two-wavelength lasing around threshold was observed under particular gain-loss condition at this specific multilayer structure of QD stacking numbers. Second, at cryogenic temperature, simultaneous two-wavelength lasing emissions switched from longer-wavelength lasing first to shorter-wavelength lasing first with increasing current injection. Non-uniform carrier distribution among chirped multilayer QD structure is evident at low temperature below 200 K from our analysis.
Temperature dependence of the electric and spintronic transport properties of Germanium on glass
(2017-10-15)
Chen, C. H.
;
Lee, C. W.
;
Yu, Y. C.
;
Lee, C. P.
;
電子工程學系及電子研究所
We present electrical spin injection and detection in p-type Ge channels using Ni/Al2O3/Ge on glass tunneling contacts. The entire structure is integrated on a glass substrate. We investigate the temperature dependence of the Hanle effect in a composite p-type Ge on glass (GeOG), using three-terminal configuration Hanle measurements; from these measurements, we observe spin accumulation up to room temperature. A spin signal of 0.3 V and a spin lifetime of 34 ps are obtained at room temperature. (C) 2017 Elsevier B.V. All rights reserved.
28V high-linearity and rugged InGaP/GaAs power HBT
(2006)
Wang, Nanlei Larry
;
Ma, Wenlong
;
Xu, Sarah
;
Camargo, Edmar
;
Sun, Xiaopeng
This paper reports on the improvement of a previously developed InGaP/GaAs HBT for 24-28V linear power operation. The improvements achieved were: application of dynamic bias circuit which improves the ACLR under WCDMA modulation; modification of device technology improving ruggedness to sustain 10:1 VSWR at 30V collector bias under P1dB driving conditions and over 6 dB of gain compression; maintenance of lifetime and reliability simultaneously. Building blocks of HBT were strung together for higher power and good scaling of performance was achieved supporting the validity of the layout approach and the thermal design. Devices delivering P-1dB = 8W under CW conditions provided ACLR = -50 dBc at 8.5 dB back-off and 16% efficiency for WCDMA signal (PAR=8.7 dB) at 2.14 GHz. Lifetime test over 3000 hours was repeated for 28V bias and 0.05mA/um(2) current density at 315 degree C junction temperature. Therefore, the InGaP/GaAs HBT technology is mature now for the high linearity power amplification.
Local structure study of GeMn recrystallization process by helium ion beam-induced epitaxial crystallization
(2015-11-01)
Chen, C. H.
;
Niu, H.
;
Lee, C. P.
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
In this study, GeMn thin films were fabricated by implantation of Mn ions at room temperature. Post-annealing was performed using 2 MeV of He+ ion irradiation. The recrystallization phenomena of the GeMn thin films were analyzed by Raman scattering. High-resolution transmission electron microscopy was also used to characterize the recrystallization process before and after ion beam annealing. A structure phase transition-like behavior of the recrystallization process of GeMn thin films was observed in the Raman spectra. (C) 2015 Elsevier B.V. All rights reserved.
Efficiency of quantum dot solar cell enhanced by improving quantum dots performance
(2015-02-01)
Weng, H. L.
;
Ueng, H. Y.
;
Lee, C. P.
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
We propose an innovative description to provide a quantitative basis to enhance the conversion efficiency of InAs/GaAs quantum dot solar cells (QDSC). A theoretical approach and numerical simulation are used to improve the performance of the quantum dots and analyze the relevance to enhance the conversion efficiency. The absorption coefficient of QDs is determined in terms of dot material, dot size, size dispersion, and shape, which are used to obtain a better match between the absorption spectrum of QDs with the portion of the solar spectrum. Either increasing the surface density for raising the photocurrent or enlarging the dot size for matching well the solar spectrum is a trade-off issue. The influence of surface density, spacer thickness, and number of dot layers on the open-circuit voltage and efficiency is discussed in detail. Moreover, volume fraction can be taken as a balance reference for the counteracting effect between J(SC) and V-OC.

學術出版;;Publications

Browse

Filters

Settings

Sort By

Results per page

🏛️國立陽明交通大學機構典藏

Search Results