WO2017030352A1 - Électrode transparente souple à structure de film mince multicouche azo/ag/azo, et son procédé de fabrication - Google Patents

Électrode transparente souple à structure de film mince multicouche azo/ag/azo, et son procédé de fabrication Download PDF

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Publication number
WO2017030352A1
WO2017030352A1 PCT/KR2016/009005 KR2016009005W WO2017030352A1 WO 2017030352 A1 WO2017030352 A1 WO 2017030352A1 KR 2016009005 W KR2016009005 W KR 2016009005W WO 2017030352 A1 WO2017030352 A1 WO 2017030352A1
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thickness
transparent electrode
metal layer
flexible transparent
azo
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PCT/KR2016/009005
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English (en)
Korean (ko)
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김준호
성태연
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고려대학교 산학협력단
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H01B1/02—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of metals or alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H01B1/06—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of other non-metallic substances
    • H01B1/08—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of other non-metallic substances oxides
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B13/00—Apparatus or processes specially adapted for manufacturing conductors or cables
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
    • H01B3/30—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B5/00—Non-insulated conductors or conductive bodies characterised by their form
    • H01B5/14—Non-insulated conductors or conductive bodies characterised by their form comprising conductive layers or films on insulating-supports

Definitions

  • the present invention relates to a flexible transparent electrode having an AZO / Ag / AZO multilayer thin film structure.
  • the flexible transparent electrode is an electrode in which a conductive pattern is formed on a flexible substrate, and is an electronic device usefully used in various fields such as a display, a transistor, a touch panel, and a solar cell.
  • ITO indium tin oxide
  • Silver is widely used in most transparent electrodes because of its high light transmittance and conductivity.
  • the ITO electrode material is replaced by the high temperature heat treatment process in the manufacturing process, the limited supply of indium, a rare metal used for the production of ITO, and the difficulty in securing flexible properties.
  • As various alternative materials for the purpose research and development on conductive oxides, carbon nanotubes, graphene, silver nanowires, and conductive polymers are being actively conducted.
  • a transparent electrode of an oxide / metal / oxide multilayer structure which does not require a heat treatment process as compared to an ITO transparent electrode requiring high temperature heat treatment. It has the advantage of being applicable to manufacturing, the process is economical, and the large area is easy.
  • Patent Document 1 a multilayer transparent electrode having a multilayer structure of silicon oxynitride / silver / silicon oxynitride (Patent Document 1), a multilayer transparent electrode having a multilayer structure of a first transparent oxide layer / silver / second transparent oxide layer ( Various techniques such as patent document 2) have been known.
  • AZO Al doped ZnO
  • Patent Document 3 a method of manufacturing a transparent conductive film coated with an AZO / Ag / AZO multilayer thin film and a technique related to a transparent conductive film formed by the method have been disclosed (Patent Document 3), and AZO / grown by a dual target DC sputtering method.
  • Non Patent Literature 1 The results of studies on the properties of the Ag / AZO multilayer structure have also been reported (Non Patent Literature 1), and the results of the research on the properties of the AZO / Ag / AZO multilayer structure deposited on the polyether sulfone substrate have also been reported.
  • Patent Document 1 Republic of Korea Patent Publication No. 10-2012-0028506
  • Patent Document 2 Republic of Korea Patent Publication No. 10-1996-0035092
  • Patent Document 3 Republic of Korea Patent Publication No. 10-2010-0089962
  • Non-Patent Document 1 Characteristics of indium-free GZO / Ag / GZO and AZO / Ag / AZO multilayer electrode grown by dual target DC sputtering at room temperature for low-cost organic photovoltaics, Solar Energy Materials & Solar Cells 93 (2009) 1994 -2002
  • Non-Patent Document 2 Properties of AZO / Ag / AZO Multilayer Thin Film Deposited on Polyethersulfone Substrate, TRANSACTIONS ON ELECTRICAL AND ELECTRONIC MATERIALS, Vol. 14, No. 1, pp. 9-11, February 25, 2013
  • the AZO / Ag / AZO multilayer structure-based flexible structure that satisfies the characteristics such as light transmittance, sheet resistance, and flexibility, which are essential for applying the AZO / Ag / AZO multilayer structure to the flexible transparent electrode, is required. It is intended to provide a transparent electrode.
  • the present invention to solve the above problems,
  • a flexible transparent electrode comprising a ZnO layer doped with Al stacked on top and bottom surfaces of the Ag metal layer, respectively.
  • the Ag metal layer has a thickness of 15 nm to 23 nm
  • the Al doped ZnO layer provides a flexible transparent electrode, characterized in that the thickness of 15 nm to 60 nm.
  • the Ag metal layer may have a thickness of 19 nm, and the Al doped ZnO layers respectively stacked on the top and bottom surfaces of the Ag metal layer may each have a thickness of 36 nm.
  • the ratio of the thickness of the Ag metal layer and the thickness of the Al-doped ZnO layer may be 1: 1 to 1: 4.
  • the ratio of the thickness of the Ag metal layer and the thickness of the Al-doped ZnO layer may be 1: 2.
  • the flexible transparent electrode has a light transmittance of 80% or more in the visible light wavelength band, 5 ⁇ / sq. It may have a sheet resistance value and a figure of merit of 10 or more.
  • the Ag metal layer and the Al-doped ZnO layer is on a flexible substrate selected from the group consisting of polyethersulfone, polyethylene terephthalate, polycarbonate, polyimide, polyethylene naphthalate and glass material Can be stacked on.
  • the Ag metal layer may have a thickness of 19 nm, and the Al doped ZnO layers respectively stacked on the top and bottom surfaces of the Ag metal layer may each have a thickness of 36 nm.
  • the ratio of the thickness of the Ag metal layer and the thickness of the Al-doped ZnO layer may be 1: 1 to 1: 4.
  • the ratio of the thickness of the Ag metal layer and the thickness of the Al-doped ZnO layer may be 1: 2.
  • the steps a) to c) may be performed by any one process selected from the group consisting of sputtering, electron beam deposition, and continuous evaporation deposition.
  • the steps a) to c) may be performed by a batch process.
  • the present invention provides a solar cell including the flexible transparent electrode.
  • the present invention provides a light emitting diode including the flexible transparent electrode.
  • a flexible transparent electrode having a high permeability comparable to that of a conventional ITO electrode, having a low sheet resistance value, and manufactured by a room temperature deposition process, which can be manufactured as it is on a polymer substrate without requiring a high temperature heat treatment.
  • FIG. 1 is a transmission electron micrograph of a transparent electrode according to the invention prepared according to the method described in Example 1.
  • FIG. 1 is a transmission electron micrograph of a transparent electrode according to the invention prepared according to the method described in Example 1.
  • FIGS. 2A and 2B are graphs showing bending test photographs and test results for the transparent electrode 2a according to Example 1 and the conventional conventional ITO electrode 2b.
  • 3A and 3B are graphs showing the results of measuring specific resistance and sheet resistance, respectively, for the five samples (3a) prepared in Example 1 and the five samples (3b) prepared in Example 2, respectively.
  • 4A and 4B are graphs showing the results of measuring the transmittances of the five samples 4a prepared in Example 1 and the five samples 4b prepared in Example 2, respectively.
  • 5A and 5B are graphs showing the results of measuring the performance indices of the five samples (5a) prepared in Example 1 and the five samples (5b) prepared in Example 2, respectively.
  • FIG. 6 is a graph depicting the surface state RMS roughness of five samples prepared according to Example 1.
  • the transparent electrode of the AZO / Ag / AZO multilayer structure has various advantages such as excellent light transmittance, low sheet resistance, and no high temperature heat treatment during the manufacturing process.
  • the transparent electrode of the AZO / Ag / AZO multilayer structure is easy to large area, the surface resistance value is reduced to a minimum for the large area, and at the same time, the necessity of preventing the light transmittance is urgently needed.
  • one of the well-known disadvantages of the AZO / Ag / AZO multilayer structure transparent electrode is that the sheet resistance value is lower than that of ITO, but the light transmittance is lowered due to the Ag layer interposed between the AZO layer and the AZO layer. Therefore, the thicker the Ag layer is, the lower the sheet resistance value is, but at the same time, the problem that the light transmittance is also one of the important problems to be overcome in the prior art.
  • the present invention as a result of repeated studies to solve the above-described problems, when the thickness of the AZO layer and Ag layer is adjusted to within a predetermined range, and excellent when the thickness ratio of the AZO layer and Ag layer is adjusted to within a predetermined range
  • the present invention has been accomplished by recognizing that sheet resistance and light transmitting properties can be achieved together.
  • a flexible transparent electrode comprising a ZnO layer doped with Al stacked on top and bottom surfaces of the Ag metal layer, respectively.
  • the Ag metal layer has a thickness of 15 nm to 23 nm
  • the Al doped ZnO layer provides a flexible transparent electrode, characterized in that the thickness of 15 nm to 60 nm.
  • the thickness of the Ag metal layer is 15 nm to 23 nm and the thickness of the AZO layer is 15 nm to 60 nm in the AZO / Ag / AZO multilayer structure, excellent sheet resistance characteristics and light transmission characteristics can be simultaneously achieved.
  • the thickness ratio of the Ag metal layer and the thickness of the AZO layer should also be present in a predetermined range, which is 1: 1 to 1: 4 ratio. It is preferably present in the range of, more preferably about 1: 2.
  • the flexible transparent electrode according to the present invention has a light transmittance of 80% or more in the visible light wavelength band, and 5 ⁇ / sq. It has a sheet resistance value of less than 10 and a figure of merit of 10 or more.
  • the AZO / Ag / AZO multilayer structure according to the present invention can be fabricated as a flexible transparent electrode by laminating on a flexible substrate selected from the group consisting of polyethersulfone, polyethylene terephthalate, polycarbonate, polyimide, polyethylene naphthalate and glass materials. have.
  • the thickness of the Ag metal layer and the AZO layer and also the thickness ratio between the two layers are as described above.
  • the deposition of the Ag metal layer and the AZO layer may be performed using conventional flexible transparent electrode manufacturing methods such as, but not limited to, sputtering, electron beam deposition and continuous evaporation deposition. It is compatible with existing ITO processes, which is one of the most important advantages in practical industrial applications.
  • the steps a) to c) may be performed by a batch type process.
  • the flexible transparent electrode manufactured according to the present invention can be usefully used for the production of solar cells, light emitting diodes, and the like which require excellent light transmittance, electrical conductivity and flexibility.
  • the flexible transparent electrode according to the present invention can be manufactured as a flat and stable surface having a large area even without high temperature heat treatment, which has a great effect on the active layer of the organic material formed on the transparent electrode, thereby increasing the efficiency of a solar cell or a light emitting diode. It will be possible to improve.
  • the PET substrate was washed, and the AZO thin film was deposited to a thickness of 36 nm using the rf sputtering method at room temperature on the substrate.
  • the AZO target had a diameter of 2 inches and a sintered ZnO target doped with 2 wt% Al was used.
  • the rf power applied to the target was 90 W, the working vacuum was maintained at 10 mTorr, the distance between the target and the substrate was about 10 cm, and 30 sccm Ar gas was used as the sputtering gas.
  • an Ag layer was deposited to a thickness of 19 nm under conditions of rf output 30 W, deposition pressure 10 mTorr, and Ar gas flow rate of 13 sccm. A 36 nm thick AZO thin film was deposited on the Ag layer.
  • FIG. 1 shows a transmission electron micrograph of a transparent electrode prepared according to the above method.
  • the transparent electrode was prepared by the same method as the above method, but four more samples having different thicknesses of Ag layers of 15, 17, 21, and 23 nm were prepared.
  • a transparent electrode was prepared in the same manner as in Example 1, but a transparent electrode in which the thicknesses of the AZO layers were laminated at 9, 18, 27, 36, and 45 nm, respectively.
  • the bending test was carried out for 1000 cycles on the transparent electrode manufactured according to Example 1 and the conventional conventional ITO electrode (thickness 100 nm), and the resistance change rate ( ⁇ R / R 0 : ⁇ R-resistance change value, R with increasing cycle) 0 -initial resistance value) was measured.
  • 2A (Example 1) and 2B (formerly conventional ITO electrodes) show graphically the bending test photographs and the results.
  • the bending test was performed by fixing one side of the sample to the fixing device and narrowing the distance of the other side, and this process was performed by repeating 1000 times. 2A and 2B, the resistance change rate increased when 1000 cycles were performed in the conventional ITO electrode, but the resistance change rate remained almost constant even when the number of cycles was increased in the transparent electrode according to the first embodiment.
  • Example 2 For the five samples prepared in Example 1 and the five samples prepared in Example 2, specific resistance and sheet resistance were measured using a four-point sheet resistance measuring instrument, respectively, and the results are shown in FIGS. 3A (Example 1) and Shown in 3b (Example 2).
  • the resistivity and sheet resistance of the samples decrease as the thickness of the Ag layer increases, and the resistivity increases as the thickness of the AZO layer increases, but in the case of sheet resistance, the AZO layer thickness tends to be almost constant. It can be seen that.
  • Example 2 For the five samples prepared in Example 1 and the five samples prepared in Example 2, the transmittance was measured at 200 to 100 nm, respectively, based on the polymer substrate, and the results are shown in FIGS. 4A (Example 1) and 4b (Example 2).
  • the transmittance of the samples tends to increase as the thickness of the Ag and AZO layers decreases in the visible region.
  • T is the transmittance of the sample and R sh is the sheet resistance value.
  • Example 1 the performance index was calculated for each of the five samples prepared in Example 1 and the five samples prepared in Example 2, and the results are shown in FIGS. 5A (Example 1) and 5B (Example 2). .
  • the samples according to Examples 1 and 2 have a significantly superior figure of merit compared to conventional ITO, in particular, the thickness of the Ag layer is 19 nm, It can be seen that the performance index of the sample having a thickness of 36 nm is the highest.
  • Figure 6 graphically shows the surface state RMS roughness of the five samples prepared according to Example 1.
  • the AZO layer has the highest RMS roughness value, and thus, has the most even surface, and thus it can be seen that excellent characteristics can be exhibited even after various organic materials are stacked thereon. have.

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  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Laminated Bodies (AREA)
  • Non-Insulated Conductors (AREA)

Abstract

La présente invention porte sur une électrode transparente souple à structure de film mince multicouche AZO/Ag/AZO, et plus précisément sur une électrode transparente souple comprenant : une couche d'Ag métallique ; et des couches de ZnO dopé Al (AZO) qui sont respectivement stratifiées sur la surface supérieure et la surface inférieure de la couche d'Ag métallique, l'épaisseur de la couche d'Ag métallique étant de 15 nm à 23 nm, et l'épaisseur des couches de ZnO dopé Al étant de 15 nm à 60 nm. La présente invention permet d'obtenir une électrode transparente souple présentant une transmittance élevée comparable à celle d'électrodes ITO classiques et présentant une faible valeur de résistance superficielle. En outre, l'électrode transparente souple est fabriquée par un processus de dépôt à température ambiante, et peut donc être fabriquée sur un substrat polymère sans nécessiter un traitement thermique à haute température.
PCT/KR2016/009005 2015-08-18 2016-08-17 Électrode transparente souple à structure de film mince multicouche azo/ag/azo, et son procédé de fabrication WO2017030352A1 (fr)

Applications Claiming Priority (2)

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KR10-2015-0116227 2015-08-18
KR1020150116227A KR20170021619A (ko) 2015-08-18 2015-08-18 AZO/Ag/AZO 다층박막 구조를 갖는 플렉시블 투명 전극 및 그 제조방법

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108336070A (zh) * 2018-02-11 2018-07-27 无锡博硕珈睿科技有限公司 电容器器件结构、电容器及电容器的制造方法

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KR20110049388A (ko) * 2009-11-05 2011-05-12 동의대학교 산학협력단 박막 형성 방법 및 발광소자
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US5667853A (en) 1995-03-22 1997-09-16 Toppan Printing Co., Ltd. Multilayered conductive film, and transparent electrode substrate and liquid crystal device using the same
KR20100089962A (ko) 2009-02-05 2010-08-13 충남대학교산학협력단 ＡＺＯ/Ａｇ/ＡＺＯ 다층박막이 코팅된 투명전도막의 제조방법
KR101145916B1 (ko) 2010-09-15 2012-05-15 경희대학교 산학협력단 플렉시블 다층 투명 전극의 제조 방법

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KR20030022835A (ko) * 2003-02-13 2003-03-17 태원필 Al-doped ZnO:TiO2 나노다층박막 습도센서
KR20110049388A (ko) * 2009-11-05 2011-05-12 동의대학교 산학협력단 박막 형성 방법 및 발광소자
KR20130058717A (ko) * 2013-05-21 2013-06-04 영남대학교 산학협력단 도핑된 ＺｎＯ 층을 포함하는 발광소자 및 그 제조방법

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JUNG, YU SUP ET AL.: "Properties of AZO/Ag/AZO Multilayer Thin Film Deposited on Polyethersulfone Substrate", TRANSACTIONS ON ELECTRICAL AND ELECTRONIC MATERIALS, vol. 14, no. 1, 25 February 2013 (2013-02-25), XP055374110 *
KJM, SANG MO ET AL.: "AZO/Ag/AZO Multilayer Prepared on Polymer Substrate", PROCEEDINGS OF THE KOREAN SOCIETY OF SEMICONDUCTOR EQUIPMENT. TECHNOTOGY, 2007 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108336070A (zh) * 2018-02-11 2018-07-27 无锡博硕珈睿科技有限公司 电容器器件结构、电容器及电容器的制造方法

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