• Title/Summary/Keyword: annealing atmosphere

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Analysis of the Structural Properties for ZnO/Sapphire(0001) Thin Films by In-situ Atmosphere Annealing (In-situ 분위기 Annealing에 따른 ZnO/Sapphire(0001) 박막의 구조적 특성 분석)

  • Wang Min-Sung;Yoo In-Sung;Park Choon-Bae
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.19 no.8
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    • pp.769-774
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    • 2006
  • In this paper the ZnO thin films, which has used spotlight of next generation short wavelength LEDs and semiconductor laser were deposited based on RF magnetron sputtering is described. The temperature at substrate and work pressure, which has implemented in sputtering process of ZnO thin films were settle down at $100^{\circ}C$ and 15 mTorr respectively. The ZnO 5N has used target. The thickness of ZnO thin films was about $1.6{\mu}m$ which was measured by SEM analysis after the sputtering process. Structural properties of ZnO thin films by in-situ and atmosphere annealing were analyzed by XRD. Transformation of grain size and surface roughness were observed by AFM. XPS spectra showed that ZnO thin film had a peak positions corresponding to the $Zn_{2p}$ and the $O_{1s}$. As form above XPS, we confirmed that post-annealing condition changed the atom ratio of Zn/O and microstructure in ZnO thin films.

Enhanced Hydrogen Gas Sensing Properties of ZnO Nanowires Gas Sensor by Heat Treatment under Oxygen Atmosphere (산소 분위기 열처리에 따른 ZnO 나노선의 상온 영역에서의 수소가스 검출 특성 향상)

  • Kang, Wooseung
    • Journal of the Korean institute of surface engineering
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    • v.50 no.2
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    • pp.125-130
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    • 2017
  • ZnO nanowires were synthesized and annealed at various temperatures of $500-800^{\circ}C$ in oxygen atmosphere to investigate hydrogen gas sensing properties. The diameter and length of the synthesized ZnO nanowires were approximately 50-100 nm and a few $10s\;{\mu}m$, respectively. $H_2$ gas sensing performance of the ZnO nanowires sensor was measured with electrical resistance changes caused by $H_2$ gas with a concentration of 0.1-2.0%. The response of ZnO nanowires at room temperature to 2.0% $H_2$ gas is found to be two times enhanced by annealing process in $O_2$ atmosphere at $800^{\circ}C$. In the current study, the effect of heat treatment in $O_2$ atmosphere on the gas sensing performance of ZnO nanowires was studied. And the underlying mechanism for the sensing improvement of the ZnO nanowires was also discussed.

Phase Changes of Vanadium Oxide Thin Films (산화 바나듐 박막의 상변화)

  • 선우진호;신인하;고경현;안재환
    • Journal of the Korean institute of surface engineering
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    • v.25 no.6
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    • pp.293-298
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    • 1992
  • Various vanadium-oxide thin films were deposited by e-beam and thermal evaporation of V2O5, V2O3, and VO2 powders. Films with thickness of $2000\AA$ were subjected to annealing at $300^{\circ}C$~$450^{\circ}C$ in N2 atmosphere for the crystallization and desification purposes. For the films deposited from V2O5 and VO2 sources, sources, Magneli (VnO2n-1$ 4\leq$ $n\leq$ 8) and VO2 phase appeared at $300^{\circ}C$, respectively, but VO2 phase also transformed into Magneli phase at $450^{\circ}C$ by severe reduction. On the contrary, VO2/VO mixed phases resulted from congruent evaporation of V2O3 unchanged after the same annealing treatment due to the balanced reduction and oxidation of VO2 and VO whcih have different equilibrium O2 pressures. It is suggested that the annealing in the controlled oxidation atmosphere or the deposition using mixed oxide sources are necessary to get the film containing VO2 phase.

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Enhancement of Photoluminescence Intensity of ZnS Nanowires by Annealing in O2 (산소 분위기에서 열처리시 ZnS 나노선의 발광 강도 변화)

  • Kwon, Jin-Up;Lee, Jong-Woo
    • Journal of the Korean institute of surface engineering
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    • v.45 no.5
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    • pp.193-197
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    • 2012
  • The influence of annealing process in an $O_2$ atmosphere on the photoluminescence (PL) spectra properties of ZnS nanowires has been investigated. ZnS nanowires with the diameters approximately 100 nm and the lengths a few tens micrometers were synthesized by evaporating ZnS powders on Si substrates while using an Au thin film as a catalyst. ZnS nanowires had an NBE emission band at 430 nm in the violet region. The emission intensity was improved drastically by a process in which ZnS nanowires were heat-treated at $500^{\circ}C$ in an $O_2$ atmosphere for 45 minutes.

Annealing of Co-Cr dental alloy: effects on nanostructure and Rockwell hardness

  • Ayyildiz, Simel;Soylu, Elif Hilal;ide, Semra;Kilic, Selim;Sipahi, Cumhur;Piskin, Bulent;Gokce, Hasan Suat
    • The Journal of Advanced Prosthodontics
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    • v.5 no.4
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    • pp.471-478
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    • 2013
  • PURPOSE. The aim of the study was to evaluate the effect of annealing on the nanostructure and hardness of Co-Cr metal ceramic samples that were fabricated with a direct metal laser sintering (DMLS) technique. MATERIALS AND METHODS. Five groups of Co-Cr dental alloy samples were manufactured in a rectangular form measuring $4{\times}2{\times}2$ mm. Samples fabricated by a conventional casting technique (Group I) and prefabricated milling blanks (Group II) were examined as conventional technique groups. The DMLS samples were randomly divided into three groups as not annealed (Group III), annealed in argon atmosphere (Group IV), or annealed in oxygen atmosphere (Group V). The nanostructure was examined with the small-angle X-ray scattering method. The Rockwell hardness test was used to measure the hardness changes in each group, and the means and standard deviations were statistically analyzed by one-way ANOVA for comparison of continuous variables and Tukey's HSD test was used for post hoc analysis. P values of <.05 were accepted as statistically significant. RESULTS. The general nanostructures of the samples were composed of small spherical entities stacked atop one another in dendritic form. All groups also displayed different hardness values depending on the manufacturing technique. The annealing procedure and environment directly affected both the nanostructure and hardness of the Co-Cr alloy. Group III exhibited a non-homogeneous structure and increased hardness ($48.16{\pm}3.02$ HRC) because the annealing process was incomplete and the inner stress was not relieved. Annealing in argon atmosphere of Group IV not only relieved the inner stresses but also decreased the hardness ($27.40{\pm}3.98$ HRC). The results of fitting function presented that Group IV was the most homogeneous product as the minimum bilayer thickness was measured (7.11 ${\AA}$). CONCLUSION. After the manufacturing with DMLS technique, annealing in argon atmosphere is an essential process for Co-Cr metal ceramic substructures. The dentists should be familiar with the materials that are used in clinic for prosthodontics treatments.

The Characteristics of Chromiun Nitride Thin-Film Strain Gauges (크롬질화박막형 스트레인 게이지의 특성)

  • Seo, Jeong-Hwan;Kim, Il-Myung;Lee, Chae-Bong;Kim, Sun-Cheol;Chung, Gwiy-Sang
    • Proceedings of the KIEE Conference
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    • 1999.07d
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    • pp.1989-1991
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    • 1999
  • This paper presents characteristics of CrN thin-film strain gauges, which were deposited on glass by DC reactive magnetron sputtering in an argon-nitrogen atmosphere(Ar-$(5{\sim}25%)N_2$). The physical and electrical characteristics of these films investigated with the thickness range $3500{\AA}$ of CrN thin films, annealing temperature $(100{\sim}300^{\circ}C)$ and annealing $(24{\sim}72hr)$. The optimized condition of CrN thin-film strain gauges were thickness range of $3500{\AA}$ and annealing condition($300^{\circ}C$, 48 hr) in Ar-10 %$N_2$ deposition atmosphere. Under optimum conditions, the CrN thin-films for strain gauge is obtained a high resistivity, ${\rho}=1147.65{\mu}{\Omega}cm$, a low temperature coefficient of resistance, TCR=$-186ppm/^{\circ}C$ and a high temporal stability with a good longitudinal, 11.17. And change in resistance after annealing for the CrN thin-films were quitely linear and stable.

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Characterization of Sol-Gel Derived Antimony-doped Tin Oxide Thin Films for Transparent Conductive Oxide Application

  • Woo, Dong-Chan;Koo, Chang-Young;Ma, Hong-Chan;Lee, Hee-Young
    • Transactions on Electrical and Electronic Materials
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    • v.13 no.5
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    • pp.241-244
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    • 2012
  • Antimony doped tin oxide (ATO) thin films on glass substrate were prepared by the chemical solution deposition (CSD) method, using sol-gel solution synthesized by non-alkoxide precursors and the sol-gel route. The crystallinity and electrical properties of ATO thin films were investigated as a function of the annealing condition (both annealing environments and temperatures), and antimony (Sb) doping concentration. Electrical resistivity, carrier concentration, Hall mobility and optical transmittance of ATO thin films were improved by Sb doping up to 5~8 mol% and annealing in a low vacuum atmosphere, compared to the undoped tin oxide counterpart. 5 mol% Sb doped ATO film annealed at $550^{\circ}C$ in a low vacuum atmosphere showed the highest electrical properties, with electrical resistivity of about $8{\sim}10{\times}10^{-3}{\Omega}{\cdot}cm$, and optical transmittance of ~85% in the visible range. Our research demonstrates the feasibility of low-cost solution-processed transparent conductive oxide thin films, by controlling the appropriate doping concentration and annealing conditions.

Dielectric Characteristics of $Ta_2O_5$ Thin Films Prepared by ECR-PECVD (ECR-플라즈마 화학 증착법에 의해 제조된 $Ta_2O_5$ 박막의 유전 특성)

  • 조복원;안성덕;이원종
    • Journal of the Korean Ceramic Society
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    • v.31 no.11
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    • pp.1330-1336
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    • 1994
  • Ta2O5 films were deposited on the p-Si(100) substrates by ECR-PECVD and annealed in O2 atmosphere. The thicknesses of Ta2O5/SiO2 layers were measured by an ellipsometer and a cross-sectional TEM. Annealing in O2 atmosphere enhanced the stoichiometry of the Ta2O5 film and reduced the impurity carbon content. Ta2O5 films were crystallized at the annealing temperatures above 75$0^{\circ}C$. The best leakage current characteristics and the maximum dielectric constant of Ta2O5/SiO2 film capacitor were observed in the specimen annealed at $700^{\circ}C$ and 75$0^{\circ}C$, respectively. The flat band voltage of the Al/Ta2O5/SiO2/p-Si MOS capacitor was varied in the range of -0.6~-1.6 V with the annealing temperature. The conduction mechanism in the Ta2O5 film, the variation of the effective oxide charge density with the annealing temperature, and the effective electric field distribution in the Ta2O5/SiO2 double layer were also discussed.

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Effect of annealing on the properties of zinc doped indium oxide(IZO) films (후열처리에 따른 Indium Zinc Oxide(IZO) 박막의 특성변화)

  • Kim, Dae-Hyun;Kim, Sang-Mo;Choi, Hyung-Wook;Kim, Kyung-Hwan;Rim, You-Seong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.260-261
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    • 2008
  • In this study, we investigated the properties of Indium Zinc Oxide (IZO) films prepared in facing targets sputtering (FTS) system at room temperature as function of oxygen contents. As as-deposited films were rapidly thermal annealing on air atmosphere of $400^{\circ}C$ for 30s. As a result, the transmittance of IZO films increased with increasing oxygen flow in the visible range. After rapidly thermal annealing to films, the optical properties of films improved than films deposited at R.T, but the electrical properties decreased. Before RTA treatment, the lowest resistivity IZO is $5.4\times10^{-4}[\Omega{\cdot}cm]$ at oxygen gas flow. But, after RTA treatment, IZO films have the value of lowest resistivity at the lower oxygen gas ratio in compare with before RTA treatment. The resistivity of IZO films is $7.29\times10^{-4}[\Omega{\cdot}cm]$ at pure argon atmosphere.

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The Effects of Process Parameters on Properties of CdS Thin Films Prepared by Solution Growth Method

  • Kim, Soo-Gil;Lee, Yong-Eui;Kim, Sang-Deok;Kim, Hyeong-Joon;Jinsoo Song;Yoon, Kyung-Hoon;Park, Byung-Ho
    • The Korean Journal of Ceramics
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    • v.3 no.1
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    • pp.57-61
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    • 1997
  • The effects of pH of solution on structural, electrical, and optical properties of CdS thin films prepared by solution growth method were investigated. With increasing pH of the solution, both crystallinity and transmittance of CdS thin film were deteriorated due to impurities and CdS particles, which were produced by homogeneous nucleation and adsorbed on the surface of CdS thin films. The films were strongly adherent to substrates and has low resistivity of 10~$10^2{\omega}cm$ regrardless of deposition conditions. After annealing at 30$0^{\circ}C$ in Ar atmosphere, the resistivity decreased due to desorption of impurity ions as well as the formation of S vacancies, but after annealing above 35$0^{\circ}C$ it increased by an agglomeration of S vacancies. After annealing in air atmosphere, the film resistivity increased because of the formation of oxide particle in grain boundaries.

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