• 제목/요약/키워드: coevaporation

검색결과 13건 처리시간 0.022초

동시증착법으로 형성한 Bi-Te 박막의 열전특성 (Thermoelectric Properties of Bi-Te Thin Films Processed by Coevaporation)

  • 최영남;김민영;오태성
    • 마이크로전자및패키징학회지
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    • 제17권4호
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    • pp.89-94
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    • 2010
  • Bi 증착원과 Te 증착원의 몰비를 변화시키며 동시증착법으로 Bi-Te 박막을 형성 후, Bi 증착원과 Te 증착원의 몰비에 따른 Bi-Te 박막의 열전특성을 분석하였다. 동시증착법으로 형성한 Bi-Te 박막은 n형 반도체로서, $-60{\sim}-80{\mu}V/K$의 Seebeck 계수를 나타내었다. Bi 증착원의 양이 30 mol%인 조건으로 동시 증착하여 Te 과잉 조성인 박막은 $5{\times}10^{-4}W/m-K^2$의 출력인자를 나타내었으며, Bi 증착원의 양이 90 mol%인 조건으로 동시 증착하여 Bi 과잉 조성인 박막은 $17.7{\times}10^{-4}W/m-K^2$의 출력인자를 나타내었다.

반응성 동시 증착법에 의한 As-grown $YBa_2Cu_3O_{7-x}$ 박막의 결정 특성 및 표면형상에 관한 연구 (Crystalline Qualities and Surface Morphologies of As-Grown $YBa_2Cu_3O_{7-x}$ Thin Films on MgO(100) Substrate by Reactive Coevaporation Method)

  • 장호연;도부안광;토신전농;청수현사;추빈량삼;강본당일;송진태
    • 한국재료학회지
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    • 제1권2호
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    • pp.93-98
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    • 1991
  • The as-grown $YBa_2Cu_3O_{7-x}$ superconducting thin films on MgO(100) substrate have been prepared by a reactive coevaporation method. The superconducting transition temperature, surface morphology and crystalline quality were examined as a function of the substrate temperature ranging from $450^{\circ}C$ to $590^{\circ}C$. From the reflection high energy electron diffraction (RHEED) analysis, it was found the film consisted of almost amorphous phase with a halo pattern deposited at the substrate temperature of $450^{\circ}C$. The film deposited at the substrate temperature of $510^{\circ}C$ consisted of polycrystalline phase, showing a broad ring pattern. On the other hand, for the film deposited at $590^{\circ}C$, RHEED showed spotty pattern indicating that this film consisted of single crystal phase. It has rough film surface due to the surface outgrowth. The surface outgrowth increased as the substrate temperature increased from $510^{\circ}C$ to $590^{\circ}C$. the surface outgrowth may be due to the anisotropic growth rate. The highest transition temperature obtained in this study was $Tc_{zero}$ of 83K with $Tc_{onset}$ of 88K for the film deposited at $590^{\circ}C$ using activated RF oxygen plasma.

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12m 길이의 YBCO 초전도선재 개발을 위한 새로운 증착방법 (Development of a new deposition system for a 12m long YBCO coated conductor)

  • 이병수;김호섭;염도준
    • 한국초전도학회:학술대회논문집
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    • 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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    • pp.319-321
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    • 1999
  • To solve the problems in the present ree1-to-reel deposition method, we have developed a new deposition system for a 12m long YBCO coated conductor. The system comprises two chambers, a reaction chamber and a evaporation chamber which are connected through window. A tan long fi tape textured by RABiTS was wound around a cylinderical sample holder of 20cm diameter. The cylinder was rotated in the reaction chamber during deposition of YBCO film by coevaporation. We'll describe the details of the performance of this system as well as the RABiTS process for a 12m long Ni tape.

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증착공정 및 환원분위기 열처리가 Sb-Te 박막의 열전특성에 미치는 영향 (Effects of Evaporation Processes and a Reduction Annealing on Thermoelectric Properties of the Sb-Te Thin Films)

  • 배재만;김민영;오태성
    • 마이크로전자및패키징학회지
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    • 제17권4호
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    • pp.77-82
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    • 2010
  • 증착공정 및 환원분위기 열처리가 p형 Sb-Te 박막의 열전특성에 미치는 영향을 연구하였다. $Sb_2Te_3$ 잉곳을 분쇄한 분말을 증착원으로 사용하여 형성한 박막은 $2.71{\times}10^{-4}W/m-K^2$, Sb와 Te 혼합분말을 증착원으로 사용하여 형성한 박막은 $0.12{\times}10^{-4}W/m-K^2$, Sb와 Te의 동시 증착으로 제조한 박막은 $0.73{\times}10^{-4}W/m-K^2$의 출력인자를 나타내었다. $300^{\circ}C$에서 2시간 유지하는 환원분위기 열처리에 의해 $Sb_2Te_3$ 잉곳을 분쇄한 분말을 증착원으로 사용하여 형성한 박막의 출력인자가 $24.1{\times}10^{-4}W/m-K^2$로 향상되었으며, Sb와 Te의 동시증착으로 제조한 박막의 출력인자는 $40.2{\times}10^{-4}W/m-K^2$로 크게 향상되었다.

Co-evaporation방법를 이용한 CuInSe2 박막 제조 및 특성분석 (Fabrication and Characterization of CuInSe2 Thin Films by Co-evaporation Method)

  • 권세한;김석기;윤경훈;안병태;송진수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 C
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    • pp.1437-1439
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    • 1996
  • In this paper, investigations on a three stage processing technique involving the co-evaporation of In-Se, Cu-Se and In-Se in this order at different deposition condition was undertaken. At first stage, we obtained good $In_{2}Se_{3}$ films by In-Se coevaporation. $In_{2}Se_{3}$ films show smooth and dense structure. And ration of In:Se was 2:3 $CulnSe_2$ thin films deposited by three stage process have shown strong adhesion on Mo coated glass substrates and good morphological properties suitable device fabrication. XWD spectra show single phase chalcopyrite $CulnSe_2$ films with strong orientation in the 112 plane. Resistivity of $CulnSe_2$ thin films was about $5{\times}10^{5}\;{\Omega}{\cdot}cm$. Surface morphology of CdS/$CulnSe_2$/Mo films was very good because of no pin holes.

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전자빔 증착법으로 제작된 ZnS:Mn 박막의 구조 및 광학적 특성 (Structural and Optical Characteristics of ZnS:Mn Thin Film Prepared by EBE Method)

  • 정해덕;박계춘;이기식
    • E2M - 전기 전자와 첨단 소재
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    • 제10권10호
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    • pp.1005-1010
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    • 1997
  • ZnS:Mn thin film was made by coevaporation with Electron Beam Evaparation(EBE) method. And structural and optical characteristics of ZnS:Mn thin films were investigated by substrate temperature annealing temperature and dopant Mn. When ZnS:Mn thin film was well deposited with cubic crystalline at substrate temperature of 30$0^{\circ}C$ its surface index was [111] and its lattice constant of a was 5.41$\AA$. Also When ZnA:Mn thin film was well made with hexagonal crystalline at substrate temperature of 30$0^{\circ}C$annealing temperature of 50$0^{\circ}C$and annealing time of 60min its miller indices were (0002) (1011), (1012) and (1120). And its lattice constant of a and c was 3.88$\AA$and 12.41$\AA$ respectively. Finally hexagonal ZnS:Mn thin film with dopant Mn of 0.5wt% had fundamental absorption wavelength of 342nm. And so its energy bandgap was about 3.62eV.

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Molecular Beam Epitaxial Growth of Oxide Single Crystal Films

  • Yoon, Dae-Ho;Yoshizawa, Masahito
    • 한국결정성장학회:학술대회논문집
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    • 한국결정성장학회 1996년도 The 9th KACG Technical Annual Meeting and the 3rd Korea-Japan EMGS (Electronic Materials Growth Symposium)
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    • pp.508-508
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    • 1996
  • ;The growth of films have considerable interest in the field of superlattice structured multi-layer epitaxy led to realization of new devices concepts. Molecular beam epitaxy (MBE) with in situ observation by reflection high-energy electron diffraction (RHEED) is a key technology for controlled layered growth on the atomic scale in oxide crystal thin films. Also, the combination of radical oxygen source and MBE will certainly accelerate the progress of applications of oxides. In this study, the growth process of single crystal films using by MBE method is discussed taking the oxide materials of Bi-Sr-Ca-Cu family. Oxidation was provided by a flux density of activated oxygen (oxygen radicals) from an rf-excited discharge. Generation of oxygen radicals is obtained in a specially designed radical sources with different types (coil and electrode types). Molecular oxygen was introduced into a quartz tube through a variable leak valve with mass flowmeter. Corresponding to the oxygen flow rate, the pressure of the system ranged from $1{\;}{\times}{\;}10^{-6}{\;}Torr{\;}to{\;}5{\;}{\times}{\;}10^{-5}$ Torr. The base pressure was $1{\;}{\times}{\;}10^{-10}$ Torr. The growth of Bi-oxides was achieved by coevaporation of metal elements and oxygen. In this way a Bi-oxide multilayer structure was prepared on a basal-plane MgO or $SrTiO_3$ substrate. The grown films compiled using RHEED patterns during and after the growth. Futher, the exact observation of oxygen radicals with MBE is an important technology for a approach of growth conditions on stoichiometry and perfection on the atomic scale in oxide. The oxidization degree, which is determined and controlled by the number of activated oxygen when using radical sources of two types, are utilized by voltage locked loop (VLL) method. Coil type is suitable for oxygen radical source than electrode type. The relationship between the flux of oxygen radical and the rf power or oxygen partial pressure estimated. The flux of radicals increases as the rf power increases, and indicates to the frequency change having the the value of about $2{\times}10^{14}{\;}atoms{\;}{\cdots}{\;}cm^{-2}{\;}{\cdots}{\;}S^{-I}$ when the oxygen flow rate of 2.0 seem and rf power 150 W.150 W.

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Cu 도핑과 열처리가 ZnTe 박막의 물성에 미치는 영향 (Influence of Cu Doping and Heat Treatments on the Physical Properties of ZnTe Films)

  • 최동일;윤세왕;김동환
    • 한국재료학회지
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    • 제9권2호
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    • pp.173-180
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    • 1999
  • Thermally evaporated ZnTe films were investigated as a back contact material for CdS/CdTe solar cells. Two deposition methods, coevaporation and double-layer methods, were used for Cu doping in ZnTe films. ZnTe layers (0.2$\mu\textrm{m}$ thick) were deposited either on glass or on CdS/CdTe substrates without intentional heating of the substrates. Post-deposition annealing was performed at 200,300 and $400^{\circ}C$ for 3,6 and 9 minutes, respectively. Band gap of 2.2eV was measured for both undoped and doped films and a slight change in the shape of absorption spectra was observed in Cu-doped samples after annealing at $400^{\circ}C$. The resistivity of as-deposited ZnTe decreased from 10\ulcorner~10\ulcornerΩcm down to 10\ulcornerΩcm as Cu concentration increased from 0 to 14 at.%. There was not a noticeable change in less of annealing temperature up to $300^{\circ}C$ whereas films annealed at $400^{\circ}C$ revealed hexagonal (101) orientations as well. Some of Cu-doped ZnTe revealed x-ray diffraction (XRD) peaks related with Cu\ulcornerTe(x=1.75~2). Grain growth was observed from about 20nm in as-deposited films to 50nm after annealing at $400^{\circ}C$ by scanning electron microscopy (SEM). Cu distribution in ZnTe films was not uniform according to Auger electron spectroscopy (AES) measurements.

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Cu(InGa)$Se_2$ 광흡수막의 두께에 따른 태양전지의 전기광학 특성 (Electrical and Optical Properties with the Thickness of Cu(lnGa)$Se_2$ Absorber Layer)

  • 김석기;이정철;강기환;윤경훈;박이준;송진수;한상옥
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 일렉트렛트 및 응용기술
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    • pp.108-111
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    • 2002
  • CIGS film has been fabricated on soda-lime glass, which is coated with Mo film. by multi-source evaporation process. The films has been prepared with thickness of 1.0 ${\mu}m$, 1.75${\mu}m$, 2.0${\mu}m$, 2.3${\mu}m$, and 3.0${\mu}m$. X-ray diffraction analysis with film thickness shows that CIGS films exhibit a strong (112) preferred orientation. Furthermore. CIGS films exhibited distinctly decreasing the full width of half-maximum and (112) preferred peak with film thickness. Also, The film's microstructure, such as the preferred orientation, the full width at half-maximum(FWHM), and the interplanar spacing were examined by X-ray diffraction. The preparation condition and the characteristics of the unit layers were as followings ; Mo back contact DC sputter, CIGS absorber layer : three-stage coevaporation, CdS buffer layer : chemical bath deposition, ZnO window layer : RF sputtering, $MgF_2$ antireflectance : E-gun evaporation

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