KR101264257B1 - Method for preparing barrier film for plastic substrate by using low frequency plasma enhanced atomic layer deposition - Google Patents
Method for preparing barrier film for plastic substrate by using low frequency plasma enhanced atomic layer deposition Download PDFInfo
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- KR101264257B1 KR101264257B1 KR1020090130898A KR20090130898A KR101264257B1 KR 101264257 B1 KR101264257 B1 KR 101264257B1 KR 1020090130898 A KR1020090130898 A KR 1020090130898A KR 20090130898 A KR20090130898 A KR 20090130898A KR 101264257 B1 KR101264257 B1 KR 101264257B1
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- 239000000758 substrate Substances 0.000 title claims abstract description 53
- 238000000231 atomic layer deposition Methods 0.000 title claims abstract description 20
- 238000000034 method Methods 0.000 title claims abstract description 19
- 239000004033 plastic Substances 0.000 title abstract description 18
- 229920003023 plastic Polymers 0.000 title abstract description 18
- 230000004888 barrier function Effects 0.000 title abstract description 17
- 239000010410 layer Substances 0.000 claims abstract description 13
- 238000004519 manufacturing process Methods 0.000 claims abstract description 11
- 239000002356 single layer Substances 0.000 claims abstract description 9
- 239000007789 gas Substances 0.000 claims description 28
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 claims description 23
- 238000010926 purge Methods 0.000 claims description 14
- 238000006243 chemical reaction Methods 0.000 claims description 13
- 239000012495 reaction gas Substances 0.000 claims description 13
- 239000000463 material Substances 0.000 claims description 12
- 239000004695 Polyether sulfone Substances 0.000 claims description 11
- 229920006393 polyether sulfone Polymers 0.000 claims description 11
- 238000000151 deposition Methods 0.000 claims description 9
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 8
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 8
- 230000008021 deposition Effects 0.000 claims description 7
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 6
- 239000006227 byproduct Substances 0.000 claims description 6
- 239000001301 oxygen Substances 0.000 claims description 6
- 229910052760 oxygen Inorganic materials 0.000 claims description 6
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 4
- GQPLMRYTRLFLPF-UHFFFAOYSA-N Nitrous Oxide Chemical compound [O-][N+]#N GQPLMRYTRLFLPF-UHFFFAOYSA-N 0.000 claims description 4
- 229910052786 argon Inorganic materials 0.000 claims description 4
- 229910052757 nitrogen Inorganic materials 0.000 claims description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 230000005540 biological transmission Effects 0.000 claims description 3
- 238000001179 sorption measurement Methods 0.000 claims description 3
- 229910052782 aluminium Inorganic materials 0.000 claims description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 2
- 229910021529 ammonia Inorganic materials 0.000 claims description 2
- 239000001307 helium Substances 0.000 claims description 2
- 229910052734 helium Inorganic materials 0.000 claims description 2
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 claims description 2
- 239000001257 hydrogen Substances 0.000 claims description 2
- 229910052739 hydrogen Inorganic materials 0.000 claims description 2
- 150000002484 inorganic compounds Chemical class 0.000 claims description 2
- 229910010272 inorganic material Inorganic materials 0.000 claims description 2
- 239000001272 nitrous oxide Substances 0.000 claims description 2
- 150000002894 organic compounds Chemical class 0.000 claims description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims 1
- 230000002265 prevention Effects 0.000 abstract description 15
- 239000002105 nanoparticle Substances 0.000 abstract description 2
- 239000010408 film Substances 0.000 description 23
- 239000010409 thin film Substances 0.000 description 14
- 230000035699 permeability Effects 0.000 description 13
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 12
- 239000002985 plastic film Substances 0.000 description 9
- 229920006255 plastic film Polymers 0.000 description 9
- 238000000576 coating method Methods 0.000 description 5
- 239000011248 coating agent Substances 0.000 description 4
- 238000005137 deposition process Methods 0.000 description 4
- JLTRXTDYQLMHGR-UHFFFAOYSA-N trimethylaluminium Chemical compound C[Al](C)C JLTRXTDYQLMHGR-UHFFFAOYSA-N 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 238000005229 chemical vapour deposition Methods 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 238000005240 physical vapour deposition Methods 0.000 description 2
- 229920000089 Cyclic olefin copolymer Polymers 0.000 description 1
- 239000004713 Cyclic olefin copolymer Substances 0.000 description 1
- 229920012266 Poly(ether sulfone) PES Polymers 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 238000009501 film coating Methods 0.000 description 1
- 125000004435 hydrogen atom Chemical class [H]* 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical group 0.000 description 1
- 239000012044 organic layer Substances 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 229920003207 poly(ethylene-2,6-naphthalate) Polymers 0.000 description 1
- 229920001230 polyarylate Polymers 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- -1 polyethylene naphthalate Polymers 0.000 description 1
- 239000011112 polyethylene naphthalate Substances 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- KKEYFWRCBNTPAC-UHFFFAOYSA-L terephthalate(2-) Chemical compound [O-]C(=O)C1=CC=C(C([O-])=O)C=C1 KKEYFWRCBNTPAC-UHFFFAOYSA-L 0.000 description 1
- 238000002834 transmittance Methods 0.000 description 1
- 238000004506 ultrasonic cleaning Methods 0.000 description 1
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- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
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- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
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- C23C16/513—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating using electric discharges using plasma jets
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Abstract
본 발명은 저주파 PEALD 장비를 이용한 플라스틱 기판용 배리어 필름 제조방법에 관한 것으로, 보다 상세하게는 플라즈마 원자층 증착(PEALD, Plasma Enhanced Atomic Layer Deposition) 장비의 챔버 내에 저주파 전원을 인가하여 플라스틱 기판에 나노 크기의 무기 배리어 단일층을 형성함으로써 기체 투과 방지 특성을 향상시킬 수 있다.The present invention relates to a method for manufacturing a barrier film for plastic substrates using low-frequency PEALD equipment, and more particularly to applying a low-frequency power in the chamber of the plasma enhanced atomic layer deposition (PEALD) equipment to a nano-sized plastic substrate. By forming the inorganic barrier monolayer of, gas permeation prevention property can be improved.
저주파 PEALD 장비, 플라스틱 기판, 배리어 층 Low Frequency PEALD Equipment, Plastic Substrates, Barrier Layers
Description
본 발명은 저주파 PEALD 장비를 이용한 플라스틱 기판용 배리어 필름 제조방법에 관한 것으로, 보다 상세하게는 플라즈마 원자층 증착(PEALD, Plasma Enhanced Atomic Layer Deposition) 장비의 챔버 내에 저주파 전원을 인가하여 플라스틱 기판에 나노 크기의 무기 배리어 단일층을 형성함으로써 기체 투과 방지 특성을 향상시킨 저주파 PEALD 장비를 이용한 플라스틱 기판용 배리어 필름 제조방법에 관한 것이다.The present invention relates to a method for manufacturing a barrier film for a plastic substrate using a low-frequency PEALD equipment, and more particularly to applying a low-frequency power in a chamber of a plasma enhanced atomic layer deposition (PEALD) equipment to a nano-sized plastic substrate. The present invention relates to a method for producing a barrier film for plastic substrates using a low frequency PEALD device having improved gas permeation prevention properties by forming an inorganic barrier monolayer.
플렉서블 디스플레이는 플라스틱 필름상에 유기발광소자(OLED), 액정표시장치(LCD) 등의 소자를 제작하여 형성된다. 상기 플라스틱 필름은 수분 및 산소와 같은 기체 차단 특성이 좋지 못하여 필름을 통해 수분 및 산소가 내부로 침투되어 산화 등에 의해 소자의 수명을 단축시키는 문제를 발생시킬 수 있으므로 이를 방지하 기 위해서는 우수한 기체 차단 특성을 나타내는 층이 플라스틱 필름상에 형성되어야 한다.The flexible display is formed by manufacturing an organic light emitting diode (OLED), a liquid crystal display (LCD), or the like on a plastic film. The plastic film has poor gas barrier properties such as moisture and oxygen, so that moisture and oxygen can penetrate the inside of the film to shorten the lifespan of the device due to oxidation, thereby preventing excellent gas barrier properties. Must be formed on the plastic film.
이에 따라 종래에는 화학기상증착(Chemical Vapor Deposition)(CVD) 공정 또는 물리기상증착(Physical vapor Deposition)(PVD) 공정 등을 적용하여 무기 박막을 형성하거나 코팅 방법에 의해 유기층을 도포하여 플라스틱 필름의 기체 차단 특성을 향상시키도록 하고 있다. Accordingly, conventionally, an inorganic thin film is formed by applying a chemical vapor deposition (CVD) process or a physical vapor deposition (PVD) process, or an organic layer is applied by a coating method to form a substrate of a plastic film. To improve the blocking characteristics.
특히 플라즈마 원자층 증착(PEALD) 방법에 의해 무기 박막을 플라스틱 필름 위에 증착할 경우 기체 투과도가 현저히 감소하는 특징이 있다. In particular, when the inorganic thin film is deposited on the plastic film by the plasma atomic layer deposition (PEALD) method, the gas permeability is significantly reduced.
종래의 PEALD 공정의 경우 대부분 고주파 전원을 사용하고 있으므로 높은 주파수로 인하여 공정의 불안정 하거나 기판의 손상 등의 문제가 발생할 수 있다.In the conventional PEALD process, since a high frequency power source is used, problems such as instability or damage to the substrate may occur due to high frequency.
본 발명의 목적은 저주파 전원을 이용한 플라즈마 원자층 증착 장비를 사용하여 기체 투과를 방지할 수 있는 플렉서블 디스플레이용 플라스틱 기판의 무기 배리어층 및 그 제조방법을 제공하는 것이다. An object of the present invention is to provide an inorganic barrier layer of a plastic substrate for flexible display and a method of manufacturing the same, which can prevent gas permeation using a plasma atomic layer deposition apparatus using a low frequency power source.
상기 목적을 달성하기 위하여, 본 발명은 수분투과도(WVTR, water vapor transmission rate)가 0.5 내지 0.004 g/m2day이고, 5 내지 50 nm의 두께를 갖는 기체 투과 방지막을 제공한다.In order to achieve the above object, the present invention provides a gas permeation prevention film having a water vapor transmission rate (WVTR) of 0.5 to 0.004 g / m 2 day and a thickness of 5 to 50 nm.
본 발명은 또한 플라즈마 원자층 증착장비를 이용하여 기체 투과 방지막을 제조함에 있어서,The present invention also provides a gas permeation prevention film using a plasma atomic layer deposition apparatus,
저주파 전원을 인가하여 기판 상에 알루미늄 옥사이드 층을 형성하는 단계를 포함하는 본 발명의 기체 투과 방지막의 제조방법을 제공한다.It provides a method for producing a gas permeation prevention film of the present invention comprising the step of applying a low frequency power source to form an aluminum oxide layer on a substrate.
상기 기판 상에 알루미늄 옥사이드 층을 형성하는 단계는 보다 구체적으로 Forming an aluminum oxide layer on the substrate is more specifically
플라스틱 기판을 플라즈마 원자층 증착장비의 반응기 내로 도입하여 반응 가스를 유입하는 단계;Introducing a plastic substrate into the reactor of the plasma atomic layer deposition apparatus to introduce a reaction gas;
상기 반응기 내에 소스 물질을 유입하여 기판 상에 흡착층을 형성하는 단계; 및Introducing a source material into the reactor to form an adsorption layer on the substrate; And
상기 반응기 내에 잔류하는 소스 물질 및 반응 부산물을 퍼지하는 단계를 포함하는 사이클을 10 내지 400회 반복하여 기판 상에 알루미늄 옥사이드 층을 형성하되, Repeating the cycle including purging the source material and the reaction by-product remaining in the reactor 10 to 400 times to form an aluminum oxide layer on the substrate,
상기 단계의 적어도 일부 동안 저주파 플라즈마를 인가하는 것을 특징으로 한다.The low frequency plasma is applied during at least part of the step.
본 발명은 또한 본 발명의 기체 투과 방지막이 증착된 플라스틱 기판 또는 상기 플라스틱 기판을 포함하는 플렉서블 디스플레이를 제공한다.The present invention also provides a plastic substrate on which the gas permeation barrier of the present invention is deposited or a flexible display including the plastic substrate.
본 발명에 따른 저주파 플라즈마 원자층 증착 장비를 이용하여 알루미늄 옥사이드 박막을 플라스틱 필름상부에 단일층을 형성함으로써 기체 투과 방지 특성을 향상하여 최소 0.004g/m2day 정도의 낮은 WVTR 투과율을 얻을 수 있다.By using a low-frequency plasma atomic layer deposition apparatus according to the present invention to form a single layer of an aluminum oxide thin film on the plastic film to improve the gas permeation prevention characteristics can be obtained a low WVTR transmittance of at least 0.004g / m 2 day.
또한, 기판의 온도와 반응가스의 퍼지시간을 조절함으로써 박막의 특성을 조절할 수 있다.In addition, the characteristics of the thin film may be controlled by adjusting the temperature of the substrate and the purge time of the reaction gas.
이하, 본 발명의 구성을 구체적으로 설명한다.EMBODIMENT OF THE INVENTION Hereinafter, the structure of this invention is demonstrated concretely.
본 발명은 수분투과도(WVTR, water vapor transmission rate)가 0.5 내지 0.004 g/m2day이고, 5 내지 50 nm의 두께를 갖는 기체 투과 방지막에 관한 것이다.The present invention relates to a gas permeation prevention membrane having a water vapor transmission rate (WVTR) of 0.5 to 0.004 g / m 2 day and having a thickness of 5 to 50 nm.
본 발명의 기체 투과 방지막은 저주파 플라즈마 원자층 증착법(low frequency plasma enhanced atomic layer deposition)을 이용하여 플렉서블 디스플레이용 플라스틱 기판 위에 증착되어 기체 투과도를 현저히 감소시킬 수 있는 무기 배리어 필름인 것을 특징으로 한다.The gas permeation prevention film of the present invention is characterized in that the inorganic barrier film that can be deposited on the plastic substrate for flexible display using a low frequency plasma enhanced atomic layer deposition method can significantly reduce the gas permeability.
상기 기체 투과 방지막은 금속산화물이라면 특별히 제한하지는 않으나, 알루미늄 옥사이드 단일층인 것이 좋다.The gas permeation barrier is not particularly limited as long as it is a metal oxide, but is preferably an aluminum oxide single layer.
상기 기체 투과 방지막은 플라스틱 기판 상에 5 내지 50 nm 크기의 두께를 가질 수 있다.The gas permeation prevention film may have a thickness of 5 to 50 nm on the plastic substrate.
상기 기체 투과 방지막은 기체 투과 방지 특성이 향상되어 0.5 내지 0.004 g/m2day 정도의 낮은 수분투과도(WVTR)를 가질 수 있다. The gas permeation prevention membrane may have a low water permeability (WVTR) of about 0.5 to 0.004 g / m 2 day due to improved gas permeation prevention characteristics.
본 발명은 또한 플라즈마 원자층 증착장비를 이용하여 기체 투과 방지막을 제조함에 있어서,The present invention also provides a gas permeation prevention film using a plasma atomic layer deposition apparatus,
저주파 전원을 인가하여 기판 상에 알루미늄 옥사이드 층을 형성하는 단계를 포함하는 본 발명의 기체 투과 방지막의 제조방법에 관한 것이다.It relates to a method for producing a gas permeation prevention film of the present invention comprising the step of applying a low frequency power source to form an aluminum oxide layer on a substrate.
상기 저주파 플라즈마 원자층 증착장비는 도 1에 도시된 바와 같이, 반응기 는 지름 50 내지 300 mm 크기의 실린더 형태이며, 기판은 정사각형 형태로 최대 크기 150×150mm 까지 장착될 수 있도록 구성되어 있다. As shown in FIG. 1, the low-frequency plasma atomic layer deposition apparatus has a cylindrical shape having a diameter of 50 to 300 mm, and a substrate is configured to be mounted to a maximum size of 150 × 150 mm in a square shape.
상기 기판 상에 알루미늄 옥사이드 층을 형성하는 단계는 보다 구체적으로 다음 단계를 포함할 수 있다:Forming an aluminum oxide layer on the substrate may more specifically include the following steps:
플라스틱 기판을 플라즈마 원자층 증착장비의 반응기 내로 도입하여 반응가스를 유입하는 단계;Introducing a plastic substrate into the reactor of the plasma atomic layer deposition apparatus to introduce a reaction gas;
상기 반응기 내에 소스물질을 유입하여 기판 상에 흡착층을 형성하는 단계; 및Introducing a source material into the reactor to form an adsorption layer on the substrate; And
상기 반응기 내에 잔류하는 소스물질 및 반응 부산물을 퍼지하는 단계를 포함하는 사이클을 10 내지 400회 반복하여 기판 상에 알루미늄 옥사이드 층을 형성하되, Repeating the cycle including purging the source material and the reaction by-products remaining in the reactor 10 to 400 times to form an aluminum oxide layer on the substrate,
상기 단계의 적어도 일부 동안 저주파 플라즈마를 인가하는 것을 특징으로 한다.The low frequency plasma is applied during at least part of the step.
상기 플라즈마 반응을 위한 반응가스로 산소, 질소, 아산화질소, 수소, 암모니아 등을 단독 또는 2종 이상 사용할 수 있으나, 이에 특별히 제한하는 것은 아니다.As the reaction gas for the plasma reaction, oxygen, nitrogen, nitrous oxide, hydrogen, ammonia, or the like may be used alone or in combination of two or more, but is not particularly limited thereto.
상기 알루미늄 옥사이드 박막을 증착하기 위한 소스물질로 알루미늄을 함유한 유기 또는 무기 화합물을 사용할 수 있다. 보다 구체적으로, TMA(트리메틸알루미늄) 등을 사용할 수 있다.An organic or inorganic compound containing aluminum may be used as a source material for depositing the aluminum oxide thin film. More specifically, TMA (trimethylaluminum) etc. can be used.
상기 기판은 테레프탈레이트, 폴리카보네이트, 사이클릭 올레핀 코폴리머, 폴리아릴레이트, 폴리에테르설폰, 또는 폴리에틸렌나프탈레이트 등을 단독 또는 2종 이상 사용할 수 있다.The substrate may be used alone or in combination of terephthalate, polycarbonate, cyclic olefin copolymer, polyarylate, polyethersulfone, polyethylene naphthalate, and the like.
상기 기판은 증착하기 전에 이소프로필알코올(IPA), 아세톤 또는 메탄올 등을 이용하여 10 내지 60분 간 초음파 세정하고, 50 내지 120℃ 오븐에서 건조한 후에 사용할 수 있으나, 이에 특별히 제한하는 것은 아니다.The substrate may be used after ultrasonic cleaning for 10 to 60 minutes using isopropyl alcohol (IPA), acetone or methanol before drying and drying in an oven at 50 to 120 ℃, but is not particularly limited thereto.
상기 반응기 내부 벽의 온도는 약 50℃로 유지한 상태에서 증착공정을 실시하고, 기판의 온도는 50℃ 내지 180℃까지 조절하여 공정을 실시할 수 있다. The temperature of the inner wall of the reactor is maintained at about 50 ℃ to perform the deposition process, the temperature of the substrate can be carried out by adjusting the temperature to 50 ℃ to 180 ℃.
상기 박막의 증착은 20℃로 항온을 유지한 상태에서 실시할 수 있다. Deposition of the thin film can be carried out while maintaining a constant temperature at 20 ℃.
반응기 내에 압력 유지와, 잔류하는 소스물질 및 반응 부산물은 아르곤, 질소, 또는 헬륨 등의 퍼지가스를 이용하여 일정한 양으로 3초 내지 15초 동안 반응기 안으로 유입시켜 퍼지시킬 수 있다.Maintaining pressure in the reactor and remaining source material and reaction by-products may be purged by introducing into the reactor in a constant amount for 3 to 15 seconds using a purge gas such as argon, nitrogen, or helium.
상기 퍼지시간은 소스물질과 반응가스의 반응 시 반응에 참여하지 않거나, 반응 후에 생기는 부산물을 기판 표면으로부터 효과적으로 제거하는데 영향을 줄 수 있어 퍼지시간이 증가함에 따라 굴절율이 증가된 치밀한 구조의 얇은 박막이 형성될 수 있다.The purge time may not participate in the reaction during the reaction of the source material and the reaction gas or may effectively remove the by-products generated after the reaction from the surface of the substrate. Can be formed.
상기 증착 공정 사이클의 횟수가 증가함에 따라 기체 투과 방지막의 두께가 증가하고, 수분투과도가 현저히 감소할 수 있다. 바람직하게는 10 내지 400회, 보다 바람직하게는 50 내지 200회가 좋다.As the number of cycles of the deposition process increases, the thickness of the gas permeation barrier may increase, and the moisture permeability may decrease significantly. Preferably it is 10-400 times, More preferably, it is 50-200 times.
상기 플라즈마는 증착 공정의 단계 전체 또는 일부 동안 인가될 수 있으며, 40 내지 500 Hz, 보다 바람직하게는 60Hz의 저주파 전원을 사용할 수 있다. The plasma may be applied during all or some of the steps of the deposition process, using a low frequency power source of 40 to 500 Hz, more preferably 60 Hz.
이러한 플라즈마의 발생 파워는 1200W 이하일 수 있다.The generated power of the plasma may be 1200 W or less.
상기 증착공정을 거친 알루미늄 옥사이드 층은 5 내지 50nm 두께의 단일층일 수 있다.The aluminum oxide layer subjected to the deposition process may be a single layer having a thickness of 5 to 50 nm.
본 발명은 또한 본 발명의 기체 투과 방지막이 증착된 플라스틱 기판 또는 상기 플라스틱 기판을 포함하는 플렉서블 디스플레이에 관한 것이다.The present invention also relates to a plastic substrate on which the gas permeation barrier of the present invention is deposited or to a flexible display including the plastic substrate.
본 발명의 기체 투과 방지막이 증착된 플라스틱 기판 또는 상기 플라스틱 기판을 포함하는 플렉서블 디스플레이는 기체 방지 특성이 향상되어 수분 및 산소가 상기 기판 내부로 침투되어 산화 등에 의한 소자의 수명 단축 등의 문제 발생을 방지할 수 있어 우수한 물성을 가질 수 있다.The plastic substrate on which the gas permeation prevention film of the present invention is deposited or the flexible display including the plastic substrate is improved in gas prevention properties to prevent moisture and oxygen from penetrating into the substrate, thereby preventing problems such as shortening the life of the device due to oxidation. It can have excellent physical properties.
이하, 본 발명에 따르는 실시예 및 본 발명에 따르지 않는 비교예를 통하여 본 발명을 보다 상세히 설명하나, 본 발명의 범위가 하기 제시된 실시예에 의해 제한되는 것은 아니다.Hereinafter, the present invention will be described in more detail through examples according to the present invention and comparative examples not according to the present invention, but the scope of the present invention is not limited to the examples given below.
<실시예 1> 저주파 플라즈마 원자층 증착을 통한 알루미늄 옥사이드 박막 형성Example 1 Aluminum Oxide Thin Film Formation by Low Frequency Plasma Atomic Layer Deposition
알루미늄 옥사이드 박막을 형성하기 위한 저주파 플라즈마 원자층 증착장비는 도 1에 나타내었다. 증착장비 내 반응기는 지름 200mm 크기의 실린더 형태이며, 기판은 정사각형 형태로 최대크기 150×150mm까지 장착될 수 있도록 구성되어 있 다. 반응기 내부 벽의 온도는 50℃로 유지한 상태로 공정을 진행하였고, 기판의 온도는 50℃에서 180℃까지 조절하여 공정을 진행하였다. 알루미늄 옥사이드 박막을 증착하기 위한 소스물질로 TMA(트리메틸알루미늄)를 사용하였으며, 증착 동안 20℃로 항온을 유지하였다. 플라즈마 반응을 위한 반응가스로는 산소를 사용하였고 챔버내 압력 유지와 소스 및 반응가스의 퍼지를 위해 아르곤을 일정한 양으로 챔버 안으로 계속 유입하였다. 플라즈마는 60Hz의 저주파 전원을 사용하였다. 소스물질 및 반응가스의 유량 및 유입시간을 조절하여 반응 사이클을 구성하였으며 이를 표 1에 나타내었다. A low frequency plasma atomic layer deposition apparatus for forming an aluminum oxide thin film is shown in FIG. 1. The reactor in the deposition equipment is in the form of a cylinder having a diameter of 200 mm, and the substrate is configured to be mounted in a square shape to a maximum size of 150 × 150 mm. The process was performed while the temperature of the reactor inner wall was maintained at 50 ℃, the temperature of the substrate was controlled by adjusting the temperature from 50 ℃ to 180 ℃. TMA (trimethylaluminum) was used as a source material for depositing the aluminum oxide thin film, and the temperature was kept at 20 ° C. during the deposition. Oxygen was used as the reaction gas for the plasma reaction, and argon was continuously introduced into the chamber in a constant amount to maintain pressure in the chamber and purge the source and the reaction gas. The plasma used a low frequency power source of 60 Hz. The reaction cycle was configured by adjusting the flow rate and the inflow time of the source material and the reaction gas and are shown in Table 1.
기판은 폴리에테르설폰(PES)을 사용하였으며 증착하기 전에 이소프로필알코올(IPA)을 이용하여 30분 간 초음파 세정을 하였으며 100℃ 오븐에서 건조한 후에 사용하였다. 또한 증착을 위한 다른 전처리는 진행하지 않았다. The substrate was made of polyethersulfone (PES) and ultrasonically cleaned for 30 minutes using isopropyl alcohol (IPA) prior to deposition and used after drying in an oven at 100 ° C. Also, no other pretreatment for deposition proceeded.
<실험예 1> 공정 사이클 별 박막 두께Experimental Example 1 Thin Film Thickness by Process Cycle
반응 사이클을 50, 100, 150, 200회로 증가시켜 알루미늄 옥사이드 막을 형성하였다. The reaction cycle was increased to 50, 100, 150, 200 to form an aluminum oxide film.
표 1에 나타난 바와 같이, 저주파 플라즈마 원자층 증착장비를 사용하여 알루미늄 옥사이드 막을 형성함에 있어 증착 사이클이 증가함에 따라 형성되는 막의 두께가 각각 15.1, 31, 39.9, 48.5nm 증가하는 것으로 나타났다. As shown in Table 1, in forming the aluminum oxide film using the low frequency plasma atomic layer deposition apparatus, the thickness of the formed film was increased by 15.1, 31, 39.9, and 48.5 nm as the deposition cycle was increased.
<실험예 2> 공정 사이클 별 기판의 수분투과도Experimental Example 2 Moisture Permeability of Substrate by Process Cycle
실시예 1에서 형성된 단일층의 알루미늄 옥사이드 막을 코팅한 후 PES 필름의 수분투과도를 코팅전과 비교하였다. 수분투과도는 MOCON PERMATRAN 3/30 장비를 이용하여 온도 37.5℃, 습도 90%에서 측정하여 결과를 표 2에 나타내었다. After coating a single layer of aluminum oxide film formed in Example 1, the moisture permeability of the PES film was compared with before coating. Moisture permeability was measured at a temperature of 37.5 ℃, humidity 90% using a MOCON PERMATRAN 3/30 equipment and the results are shown in Table 2.
표 2에 나타난 바와 같이, 공정 사이클이 증가함에 따라 알루미늄 옥사이드 막이 형성된 후에 수분투과도가 현저히 감소하여 필름의 수분차단 특성이 상당히 향상되는 것을 알 수 있다.As shown in Table 2, it can be seen that as the process cycle increases, the moisture permeability is significantly reduced after the aluminum oxide film is formed, thereby significantly improving the moisture barrier property of the film.
<실험예 3> 반응가스 퍼지시간 별 기판의 굴절률Experimental Example 3 Refractive Index of Substrate by Reaction Gas Purge Time
원자층 증착 공정 동안에 소스 및 반응가스를 유입시킨 후에 아르곤 가스의 유입시간을 3, 6, 10, 15초로 증가시켜 알루미늄 옥사이드 막을 형성하였다. 원자층 증착 방법은 통상적으로 기존의 CVD 방법과는 달리 기판표면상의 한정된 수의 부위에서 반응이 이루어진다. 따라서 소스와 반응가스가 유입된 후 충분한 퍼지가 이루어질 경우 반응에 참여하지 않거나 혹은 반응 후에 생기는 부산물을 기판 표면으로부터 효과적으로 제거함으로써 원자층 박막 형성에 기여할 수 있다. After the source and the reaction gas were introduced during the atomic layer deposition process, the inflow time of the argon gas was increased to 3, 6, 10, and 15 seconds to form an aluminum oxide film. Atomic layer deposition methods typically react at a limited number of sites on the substrate surface, unlike conventional CVD methods. Therefore, if sufficient purge is performed after the source and the reaction gas are introduced, it may not contribute to the reaction or effectively remove the by-products generated after the reaction from the substrate surface, thereby contributing to the formation of the atomic layer thin film.
표 3에 나타난 바와 같이, 50 사이클인 경우 10초 퍼지시간에서, 100 사이클인 경우 6초에서 플라스틱 필름 위에 굴절율이 가장 크고 얇은 막을 형성함을 알 수 있었다. As shown in Table 3, it was found that the largest refractive index on the plastic film was formed on the plastic film at 10 seconds purge time for 50 cycles and 6 seconds for 100 cycles.
<실험예 4> 알루미늄 옥사이드 박막 코팅에 따른 플라스틱 필름의 수분투과도Experimental Example 4 Moisture Permeability of Plastic Film According to Aluminum Oxide Thin Film Coating
실험예 3에서 형성된 단일층의 알루미늄 옥사이드 박막을 코팅한 후 PES 필름의 수분투과도를 코팅전과 비교하였다. 수분투과도는 MOCON PERMATRAN 3/30 장비를 이용하여 온도 37.5℃, 습도 90%에서 측정하여 결과를 표 4에 나타내었다. After coating a single layer of aluminum oxide thin film formed in Experimental Example 3, the moisture permeability of the PES film was compared with before coating. Moisture permeability was measured at 37.5 ℃ temperature, 90% humidity using a MOCON PERMATRAN 3/30 equipment and the results are shown in Table 4.
표 4에 나타난 바와 같이, 알루미늄 옥사이드 막이 형성된 후에 수분투과도가 현저히 감소하여 필름의 수분차단 특성이 상당히 향상되는 것을 알 수 있다. As shown in Table 4, it can be seen that the moisture permeability is significantly reduced after the aluminum oxide film is formed, thereby significantly improving the moisture barrier properties of the film.
또한, 퍼지시간이 10내지 15초인 시료의 경우에 보다 치밀한 구조로 박막이 형성됨으로써 측정감도 수준의 낮은 수분투과도를 나타냄을 알 수 있다. In addition, in the case of the sample having a purge time of 10 to 15 seconds, it can be seen that the thin film is formed in a more dense structure, thereby exhibiting a low moisture permeability of the measurement sensitivity level.
도 1은 본 발명의 저주파 플라즈마 원자층 증착장비를 도시한 것이다.Figure 1 shows a low frequency plasma atomic layer deposition apparatus of the present invention.
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