• Title/Summary/Keyword: trilayer structure

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Optical Recording Properties of $(Te_{86}Se_{14})_{50}Bi_{50}$ Thin Films with Trilayer Structure (삼중층 구조를 갖는 $(Te_{86}Se_{14})_{50}Bi_{50}$ 박막의 광기록 특성)

  • Kim, Byeong-Hoon;Lee, Hyun-Yong;Lee, Young-Jong;Chung, Hong-Bae
    • Proceedings of the KIEE Conference
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    • 1988.11a
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    • pp.164-167
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    • 1988
  • This paper reports optical properties and hole formation of a 488nm-optimumed trilayer structure utiluzed Te-based thin films as a recording layer, and the application of trilayer to 830nm. The optical recording characteristics of metallic recording media are enhanced significantly by incoporating the metal (Al) layer into an antireflection trilayer structure. Due to the interference condition inherent in the design of the trilayer structure, reflectance from holes is ranked a low fraction. the hole formation is carried out by laser by $Ar^+$ laser(488nm). For 20nsec laser pulse duration, the hole opening threshold power of $(Te_{86}Se_{14})_{50}Bi_{50}$ trilayer is lower than that of monolayor that used in this experiments. Hole shapes of the whole sample were clean. For the application of the diode laser, the thickness of dielectric is varied by$\lambda$/4n. In order to compare the monolayer with the trilayer reflectance was measured.

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Simulation of Optical Characteristics of 1.3 μm GaAs-Based GaAsSb/InGaAs and GaAsSb/InGaNAs Quantum Well Lasers for Optical Communication (광통신용 GaAs 기반 1.3 μm GaAsSb/InGaAs와 GaAsSb/InGaNAs 양자우물 레이저의 광학적특성 시뮬레이션)

  • Park, Seoung-Hwan
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.24 no.1
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    • pp.1-6
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    • 2011
  • Optical gain characteristics of $1.3{\mu}m$ type-II GaAsSb/InGaNAs/GaAs trilayer quantum well structures were studied using multi-band effective mass theory. The results were compared with those of $1.3{\mu}m$ GaAsSb/InGaNAs/GaAs trilayer quantum well structures. In the case of $1.3{\mu}m$ GaAsSb/InGaNAs/GaAs trilayer quantum well structure, the energy difference between the first two subbands in the valence band is smaller than that of $1.3{\mu}m$ GaAsSb/InGaNAs/GaAs trilayer quantum well structure. Also, $1.3{\mu}m$ GaAsSb/InGaNAs/GaAs trilayer quantum well structure shows larger optical gain than $1.3{\mu}m$ GaAsSb/InGaNAs/GaAs trilayer quantum well structure. This means that GaAsSb/InGaNAs/GaAs system is promising as long-wavelength optoelectronic devices for optical communication.

Antireflection Structures and Optical Recording Properties of Te-based Alloy Thin Films (Te계 합금 박막의 Antireflection 구조와 광기록 특성)

  • Lee, Hyun-Yong;Choi, Dae-Young;Lee, Young-Jong;Chung, Hong-Bae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1988.05a
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    • pp.74-77
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    • 1988
  • This paper reports the properties of antireflection structure and hole formation of Te-based systems. The optical-recording characteristics of metallic recording media are enhanced significantly by incorporating the metal(Al) layer into an antreflection trilayer structure. Due to the interface condition inherent in the design of the trilayer structure, reflectivity from holes is ranked low fraction (<10%). The hole formation is carried by $Ar^+$ Laser(488nm). For 20nsec pulse duration, hole opening power(threschold) of $(Te_{86}Se_{14})_{50}Bi_{50}$ trilayer is lower than that of monolayer that used in this experiment. Hole shapes of the whole sample were clean.

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Planar Hall Resistance Sensor for Monitoring Current

  • Kim, KunWoo;Torati, Sri Ramulu;Reddy, Venu;Yoon, SeokSoo
    • Journal of Magnetics
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    • v.19 no.2
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    • pp.151-154
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    • 2014
  • Recent years have seen an increasing range of planar Hall resistive (PHR) sensor applications in the field of magnetic sensing. This study describes a new application of the PHR sensor to monitor a current. Initially, thermal drift experiments of the PHR sensor are performed, to determine the accuracy of the PHR signal output. The results of the thermal drift experiments show that there is no considerable drift in the signals attained from 0.1, 0.5, 1 and 2 mA current. Consequently, the PHR sensor provides adequate accuracy of the signal output, to perform the current monitoring experiments. The performances of the PHR sensor with bilayer and trilayer structures are then tested. The minimum detectable currents of the PHR sensor using bilayer and trilayer structures are $0.51{\mu}A$ and 54 nA, respectively. Therefore, the PHR sensor having trilayer structure is the better choice to detect ultra low current of few tens nanoampere.

The optical analysis of Te-based ART structure for the optical recording media (광기록 매질로 이용되는 Te계 ART구조의 광학적 해석)

  • 이성준;박태성;정홍배
    • Electrical & Electronic Materials
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    • v.7 no.3
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    • pp.220-224
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    • 1994
  • In this study, we discussed the optical property to find the optimal condition of Te-based antireflection trilayer(ART) structure for a high density optical recording. It was found that the optical property was improved by suggesting the environmental parameters satisfied the optimum condition. As the results, the optimized(.lambda.=8.000${\AA}$.) thickness of the recording layer is 27${\AA}$, and the 1st and 2nd minimum ART conditions of dielectric layers are 1080${\AA}$, 3820${\AA}$, respectively. And the high SNR, the contrast ratio and the sensitivity are achieved by using the ART conditions.

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Antireflective ZTO/Ag bilayer-based transparent source and drain electrodes for highly transparent thin film transistors

  • Choe, Gwang-Hyeok;Kim, Han-Gi
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2012.05a
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    • pp.110.2-110.2
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    • 2012
  • We reported on antireflective ZnSnO (ZTO)/Ag bilayer and ZTO/Ag/ZTO trilayer source/drain (S/D) electrodes for all-transparent ZTO channel based thin film transistors (TFTs). The ZTO/Ag bilayer is more transparent (83.71%) and effective source/drain (S/D) electrodes for the ZTO channel/Al2O3 gate dielectric/ITO gate electrode/glass structure than ZTO/Ag/ZTO trilayer because the bottom ZTO layer in the trilayer increasea contact resistance between S/D electrodes and ZTO channel layer and reduce the antireflection effect. The ZTO based all-transparent TFTs with ZTO/Ag bilayer S/D electrode showed a saturation mobility of 4.54cm2/Vs and switching property (1.31V/decade) comparable to TTFT with Ag S/D electrodes.

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Effect of Calcium Doping in Low Angle Grain Boundaries of $YBa_2Cu_3O_{7-\delta}$ on Textured Metal Substrates

  • Kang, B.W.;A. Goyal;F.A. List;D.K. Christen;H. R. Kerchner;S. Sathyamurthy;Lee, D.F.;Martin, P.M.;Koreger, D.M.
    • Progress in Superconductivity
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    • v.4 no.1
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    • pp.10-13
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    • 2002
  • We report the effect of Ca doping in $YBa_2Cu_3O_{7-\delta}$ (YBCO) thin films grown on the Rolling- Assisted, Biaxially Textured Substrates (RABiTS) with the architecture of $CeO_2/YSZ/CeO_2/Ni$. Critical currents of bilayer and trilayer structures of $YBCO/Y_{0.7}Ca_{0.3}Ba_2Cu_3O_{7-\delta}$/(YCaBCO) as well as undoped YBCO for comparison have been measured in a wide range of temperatures and fields. For $6-8^{\circ}$ grain boundaries, 30% Ca-doping in bilayer structure enhances $J_c$ as high as 35%. The enhancement is larger at low temperatures and at magnetic fields. On the other hand, 30% Ca-doping in trilayer structure reduces $J_c$ as high as 60%. Combined with slightly lower $T_c$, this indicates that Ca is overdoped in this structure and degrades GBs.

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Electronic Structures and Magnetic Properties of Fe/Si/Fe Trilayer

  • Park, Jin-Ho;Youn, Suk-Ju;Min, Byung-Il;Yi, Jae-Yel
    • Journal of Magnetics
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    • v.1 no.1
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    • pp.4-8
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    • 1996
  • Employing the LMTO band method, we have studied electronic and magnetic properties of Fe/Si/Fe trilayer in which the z-direction is chosen to be (111) direction of FeSi with B2 phase, We have also determined electronic structure of bulk FeSi, as a reference material. The ground state of FeSi is paramagnetic insulator with a band gap of 0.05 eV. Band structures of Fe/Si/Fe with varying the thickness of the spacer layer reveal that the spacer layer is metallic, and the states along the growth direction do not disperse much reflecting a two-dimensional nature. Magnetic moment of Fe atom in the interfacial layer of Fe/Si/Fe is reduced a lot as compared to the bulk value, suggesting a strong hybridization between Fe and Si states. The geometry of the Fermi surface indicates that the magnetic coupling period of ~8ML (monolayers) in Fe/Si/Fe is explained with a short Fermi wave vector of bcc Si.

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