• Title/Summary/Keyword: Annealing temperature

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Hydrothermal Growth and Characteristics of ZnO Nanorods on R-plane Sapphire Substrates

  • Kim, Min-Su;Kim, So-A-Ram;Nam, Gi-Ung;Park, Hyeong-Gil;Yun, Hyeon-Sik;Im, Jae-Yeong
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2012.05a
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    • pp.236-237
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    • 2012
  • ZnO nanorods were grown on R-plane sapphire substrates with the seed layers annealed at different temperature. The effects of annealing temperature for the seed layers on the properties of the ZnO nanorods were investigated by scanning electron microscopy, X-ray diffraction, UV-visible spectroscopy, and photoluminescence. For the as-prepared seed layers, the ZnO nanorods and the ZnO nanosheets were observed. Only the ZnO nanorods were grown as the annealing temperature was above $700^{\circ}C$. The optical transmittance in the UV region was almost zero while that in the visible region was gradually increased as the annealing temperature increased to $700^{\circ}C$. The optical band gap of the ZnO nanorods was increased as the annealing temperature increased to $700^{\circ}C$. In the visible region, the refractive index was decreased with increasing the wavelength, and the extinction coefficient was decreased as the annealing temperature increased to $700^{\circ}C$. The non-linear exciton radiative life time of the FX emission peak was established by cubic equation. The values of Varshni's empirical equation fitting parameters were ${\alpha}=4{\times}10^{-3}eV/K$, ${\beta}=1{\times}10^4K$, and $E_g(0)=3.335eV$ and the activation energy was found to be about 94.6 meV.

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Effect of RTA temperature on the leakage current characteristics of PZT thin films (RTA 온도가 PZT 박막의 누설전류에 미치는 영향)

  • 김현덕;여동훈;임승혁;송준태
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.709-712
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    • 2001
  • The effects of post annealing temperature by the Rapid Thermal Annealing(RTA) on the electrical properties of Pb(Zr,Ti)O$_3$(PZT) thin film were investigated. Analyses by the RTA treatments reveled that the leakage current of PZT thin films strongly depend on heating temperature and time. It was found that leakage current properties of PZT capacitor were changed by heating temperature during the RTA annealing. On Pt/Ti/Si substrates, PZT films are deposited at 350 $^{\circ}C$ by rf magnetron sputtering. The X-ray diffusion (XRD) was confirmed the formation of PZT thin film. Leakage current characteristics were improved with decreasing the post annealing temperature of PZT thin film. RTA annealed film on the 700$^{\circ}C$ shows ferroelectric and electrical properties with a remanent polarization of 12.4${\mu}$C/$\textrm{cm}^2$ coercive field of 117kV/cm, leakage current J= 6.2${\times}$10$\^$-6/ A/$\textrm{cm}^2$

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A Study on the Microwave Dielectric Properties of 0.182BaO-0.818TiOS12T Ceramics (0.182BaO-0.818TiO2 세라믹스의 마이크로파 유전특성에 관한 연구)

  • 박인길;이영희;윤석진;정형진
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.43 no.3
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    • pp.442-446
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    • 1994
  • In this study, microwave dielectric properties of 0.182BaO-0.818TiOS12T ceramics were investigated with sintering temperature and annealing time, and the application for the microwave dielectric resonator was studied. In the specimen simtered at 1400[$^{\circ}C$], dielectric constant, unloaded Q and temperature coefficient of resonant frequency had good values of 35.36, 5692, -4.43[ppm/$^{\circ}C$], respectively. The specimen which temperature coefficient of resonant frequency($\tau$f) was vared positive to negative value was selected, thereafter microwave dielctric properties was investigated with annealing time(0~4[hr]) in the fixed annealing temperature of 1350[$^{\circ}C$]. Increasing the annealing time, dielectric constant and unloaded Q were increased and temperature coefficient of resonant frequency was decreased.

AFM and C-F Properties of Ceramic Thin Film with Annealing Method (열처리 방법에 따른 세라믹 박막의 AFM 및 C-F 특성)

  • Choi, Woon-Shik
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.28 no.9
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    • pp.598-601
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    • 2015
  • The $Sr_{0.7}Bi_{2.3}Nb_2O_9(SBN)$ thin films are deposited on Pt electrode($Pt/Ti/SiO_2/Si$) using RF sputtering method at various deposition temperature. The deposition temperature of optimum was $300^{\circ}C$. SBN thin films were annealed at $500{\sim}700^{\circ}C$ using furnace and RTA, respectively. The surface roughness showed about 2.42 nm in annealing temperature($600^{\circ}C$) of furnace. The capacitance density of SBN thin films were increased with the increase of annealing temperature. The maximum capacitance density of $0.7{\mu}F/cm^2$ was obtained by annealing temperature($700^{\circ}C$). The frequency dependence of dielectric loss showed about 0.03 in frequency ranges of 1~1,000 kHz.

Characteristics of AZO(ZnO:Al) thin film with the substrate temperature and post-annealing (기판온도 및 후 열처리에 따른 AZO(ZnO:Al) 박막의 특징)

  • Kim, Kyung-Hwan;Cho, Bum-Jin;Keum, Min-Jong;Son, In-Hwan;Choi, Hyung-Wook;Choi, Myung-Kyu
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.432-433
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    • 2005
  • In this study, Al doped ZnO(AZO) thin film were prepared on glass substrates by FTS(Facing Targets Sputtering) system. We investigated electrical, optical and structural properties of AZO thin film with the substrate temperature of the R.T, $100^{\circ}C$, $200^{\circ}C$ and the post-annealing. The crystallinity of AZO thin film was increased with increasing the substrate temperature and post-annealing temperature $600^{\circ}C$. The remarkable change of the resistivity with the substrate temperature didn't found and the resistivity with post-annealing was increased slightly.

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Electrical and Optical Properties of BZO Thin Films Deposited by RF Magnetron Sputtering with Various Annealing Temperatures (열처리 온도에 따른 BZO 박막의 전기적 및 광학적 특성)

  • Seong-Jun Kang;Yang-Hee Joung
    • The Journal of the Korea institute of electronic communication sciences
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    • v.19 no.1
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    • pp.47-52
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    • 2024
  • The effects of annealing temperature on the optical and electrical properties of BZO thin films, grown on glass substrate, have been investigated. Analysis of the XRD shows that regardless of the annealing temperature, all BZO thin films indicate the c-axis orientation. The full width of half maximum (FWHM) decreases from 1.65 to 1.07° as the annealing temperature increases from 400 to 600℃. The average transmittance in the visible light region showed a high value of 85% without significantly affecting the annealing temperature. The results of Hall effect measurements indicate that the carrier concentration and mobility increased and the resistivity decreased as the annealing temperature increased. The resistivity and the carrier concentration of the BZO thin films annealed 600℃ were 9.75×10-2 Ω·cm and 4.21×1019 cm-3 respectively, showing the best value. The optimization of deposition and annealing conditions will certainly make the BZO thin films promising materials for the application to the next generation of optoelectronic devices.

Effects of Mill Annealing Temperature on the Microstructure and Hardness of Ti-6Al-4V Alloys (밀어닐링 온도가 Ti-6Al-4V 합금의 미세조직 및 경도에 미치는 영향)

  • Seo, Seong-ji;Kwon, Gi-hoon;Choi, Ho-joon;Lee, Gee-young;Jung, Min-su
    • Journal of the Korean Society for Heat Treatment
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    • v.32 no.6
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    • pp.263-269
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    • 2019
  • The mechanism of microstructure and hardness changes during mill annealing of Ti-6Al-4V alloy was investigated. The annealing heat treatments were performed at $675{\sim}795^{\circ}C$ in vacuum for 2 hours, followed by air cooling. The microstructure was observed by using an optical microscope and X-ray diffraction, and hardness was measured by using a Rockwell hardness tester and micro Vickers hardness tester. The average grain size becomes smaller at $675^{\circ}C$ to $735^{\circ}C$ due to the formation of new grains rather than grain growth, but becomes larger at $735^{\circ}C$ to $795^{\circ}C$ due to growth of the already-formed grains rather than formation of new grains. The mill annealing temperature becomes higher, the ${\beta}$ phase fraction decreases and ${\alpha}$ phase fraction increases at room temperature. This is because the higher annealing temperature, the smaller amount of V present in the ${\beta}$ phase, and thus the ${\beta}$ to ${\alpha}$ transformation occurs more easily when cooled to room temperature. As the mill annealing temperature increases, the hardness value tends to decrease, mainly due to resolution of defects such as dislocations from $675^{\circ}C$ to $735^{\circ}C$ and due to grain growth from $735^{\circ}C$ to $795^{\circ}C$, respectively.

The Effect of Thermal Annealing Process on Fermi-level Pinning Phenomenon in Metal-Pentacene Junctions

  • Cho, Hang-Il;Park, Jin-Hong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.290.2-290.2
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    • 2016
  • Recently, organic thin-film transistors have been widely researched for organic light-emitting diode panels, memory devices, logic circuits for flexible display because of its virtue of mechanical flexibility, low fabrication cost, low process temperature, and large area production. In order to achieve high performance OTFTs, increase in accumulation carrier mobility is a critical factor. Post-fabrication thermal annealing process has been known as one of the methods to achieve this by improving the crystal quality of organic semiconductor materials In this paper, we researched the properties of pentacene films with X-Ray Diffraction (XRD) and Atomic Force Microscope (AFM) analyses as different annealing temperature in N2 ambient. Electrical characterization of the pentacene based thin film transistor was also conducted by transfer length method (TLM) with different annealing temperature in Al- and Ti-pentacene junctions to confirm the Fermi level pinning phenomenon. For Al- and Ti-pentacene junctions, is was found that as the surface quality of the pentacene films changed as annealing temperature increased, the hole-barrier height (h-BH) that were controlled by Fermi level pinning were effectively reduced.

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Investigation of thermal annealing effects on the optical transparency and luminescent characteristics of Eu-doped Y2O3 thin films

  • Chung, Myun Hwa;Kim, Joo Han
    • Journal of Ceramic Processing Research
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    • v.20 no.4
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    • pp.431-435
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    • 2019
  • The thermal annealing effects on the optical transparency and luminescent characteristics of the Eu-doped Y2O3 thin films have been investigated. The as-deposited Y2O3:Eu films exhibited an optical band gap of 5.78 eV with a transparency of 89 % at a wavelength of 550 nm. As the annealing temperature increased from 1000 to 1300 ℃, the optical band gap and transparency of the films decreased from 5.77 to 4.91 eV and from 86.8 to 64.5 % at 550 nm, respectively. The crystalline quality of the films was improved with increasing annealing temperature. The annealed Y2O3:Eu films emitted a red-color photoluminescence (PL) with the highest emission peak near 612 nm. The PL intensity was increased with increasing annealing temperature to 1200 ℃, resulting from the improvement in the crystalline quality of the films. The PL intensity was decreased with further increasing temperature above 1200 ℃ due to the formation of Y2SiO5 phase by the reaction of the film with the quartz substrate.

Effect of Annealing Temperature on the Durability of PEMFC Polymer Membrane (PEMFC 고분자막의 어닐링 온도가 내구성에 미치는 영향)

  • Lee, Mihwa;Oh, Sohyeong;Park, Yujun;Yoo, Donggeun;Park, Kwonpil
    • Korean Chemical Engineering Research
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    • v.60 no.1
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    • pp.7-11
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    • 2022
  • In the membrane forming process of a proton exchange membrane fuel cell (PEMFC), drying and annealing heat treatment processes are required for performance and durability. In this study, the optimal annealing temperature for improving the durability of the polymer membrane was studied. It was annealed in the temperature range of 125~175 ℃, and thermal stability and hydrogen permeability were measured as basic data of durability at each annealing temperature. The electrochemical durability was analyzed by Fenton reaction and open circuit voltage (OCV) holding. The annealing temperature of 165 ℃ was the optimal temperature in terms of thermal stability and hydrogen permeability. In the Fenton reaction, the fluorine emission rate of the membrane annealed at 165 ℃ was the lowest, and the lifespan of the membrane annealed at 165 ℃ was the longest in the OCV holding experiment, confirming that 165 ℃ was the optimal temperature for the durability of the polymer membrane.