JP3684614B2 - Organic thin film light emitting device and method for manufacturing the same - Google Patents
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- 239000010409 thin film Substances 0.000 title claims description 27
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- 229910052782 aluminium Inorganic materials 0.000 claims description 8
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- 229910052749 magnesium Inorganic materials 0.000 claims description 5
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- TVIVIEFSHFOWTE-UHFFFAOYSA-K tri(quinolin-8-yloxy)alumane Chemical compound [Al+3].C1=CN=C2C([O-])=CC=CC2=C1.C1=CN=C2C([O-])=CC=CC2=C1.C1=CN=C2C([O-])=CC=CC2=C1 TVIVIEFSHFOWTE-UHFFFAOYSA-K 0.000 description 1
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- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K50/00—Organic light-emitting devices
- H10K50/80—Constructional details
- H10K50/805—Electrodes
- H10K50/82—Cathodes
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Description
【０００１】
【産業上の利用分野】
本発明は各種表示装置の発光源として用いられる有機薄膜発光素子の陰極およびその製造方法に関する。
【０００２】
【従来の技術】
従来のブラウン管に代わるフラットパネルディスプレイの需要の急増に伴い、各種表示素子の開発および実用化が精力的に進められている。エレクトロルミネッセンス素子（以下ＥＬ素子と称する）もこうしたニーズに即するものであり、特に素子全体が固体より構成されていること、自ら発光することにより他のディスプレイにはない高解像度および高視認性により注目を集めている。
【０００３】
現在実用化されているものは、主に発光層にＺｎＳ／Ｍｎ系を用いた無機材料からなるＥＬ素子である。しかしこの種の無機ＥＬ素子は発光に必要な駆動電圧が２００Ｖ程度と高いために駆動方法が複雑となり、製造コストが高いといった問題点がある。また青色発光の効率が低いため、フルカラー化が困難である。
これに対して有機材料を用いた薄膜発光素子は、発光に必要な駆動電圧を大幅に低減でき、かつ各種発光材料の添加により、フルカラー化の可能性を持つことから、近年活発に研究が行われている。
【０００４】
特に、陽極／正孔注入層／発光層／陰極からなる積層型において、発光剤にトリス（８−ヒドロキシキノリン）アルミニウムを、正孔注入剤に１，１−ビス（４−Ｎ，Ｎ−ジトリルアミノフェニル）シクロヘキサンを用いることにより、１０Ｖ以下の印加電圧で１０００ｃｄ／ｍ2 以上の輝度を得られたという報告がなされて以来、開発に拍車がかけられた（Appl.Phys.Lett. 51, 913 (1987)）。
【０００５】
以上のように有機材料を用いた薄膜発光素子は低電圧駆動やフルカラー化などの可能性を強く示唆しているものの、性能面では解決しなければならない課題が多く残されている。特に長時間駆動に伴う特性劣化の問題は乗り越えねばならない課題である。該特性劣化の原因の一つとして、陰極の安定性の不足が挙げられる。陰極材料は、電子注入性を向上するために仕事関数の小さな金属が好ましいが、そのために酸化されやすいという問題を抱えている。
【０００６】
【発明が解決しようとする課題】
この問題に対処するために陰極を仕事関数の大きい金属元素との合金にして用いる（特開平２−１５５９５号公報）方法、あるいは仕事関数の小さい金属または合金上に仕事関数の大きい金属および合金を積層する（特開平４−２３３１９５号公報）等の手法が提案されている。しかしながら前者は仕事関数の小さい金属元素（例えばＭｇ）を多量に含まなければ電子注入性が確保されないために仕事関数の大きい金属元素（例えばＡｇ）の組成割合が小さくそのために安定性が充分でない。また後者は有機層と金属または合金との界面における酸化を防ぐことは困難である等の課題を抱えている。
【０００７】
この発明は上述の点に鑑みてなされ、その目的は電子注入性が高い上に化学的安定性にも優れる陰極を開発することにより特性と信頼性に優れる有機薄膜発光素子およびその製造方法を提供することにある。
【０００８】
【課題を解決するための手段】
上述の目的はこの発明によれば、絶縁性透明基体上に陽極、正孔注入層と発光層と電子注入層のうちの少なくとも発光層からなる有機層、陰極を積層してなる有機薄膜発光素子において、陰極がアルミニウムを主成分とし、副成分としてシリコン元素および仕事函数がアルミニウムの仕事函数よりも小さいＭｇ、Ｃ a 、Ｍｎ、Ｂａ、Ｌａから選ばれる元素を含有し、かつシリコン元素の含有量が０．１重量％ないし３．００重量％であることにより達成される。
また、絶縁性透明基体上に陽極、正孔注入層と発光層と電子注入層のうちの少なくとも発光層からなる有機層、陰極を積層してなる有機薄膜発光素子において、陰極がアルミニウムを主成分とし、副成分としてシリコン元素および仕事函数がアルミニウムの仕事函数よりも小さいＭｇ、Ｃ a 、Ｍｎ、Ｂａ、Ｌａから選ばれる元素を含有し、かつシリコン元素の含有量が０．１重量％ないし３．００重量％である有機薄膜発光素子の製造方法において、陰極はフラッシュ蒸着法により成膜されることにより達成される。
【０００９】
また前記した有機薄膜発光素子の陰極はフラッシュ蒸着法により成膜されるとすることにより達成される。
また陰極のＡｌ元素の含有量は、好ましくは９０重量％以上であり、より好ましくは９５重量％以上である。
陰極のＳｉ元素の含有量は好ましくは０．０１ないし３．００重量％であり、より好ましくは０．１ないし１．００重量％の範囲にある。
【００１０】
アルミニウム金属元素の仕事函数４．２ｅＶよりも小さい仕事函数を有する元素としては経済性の見地からＭｇ、Ｃ a 、Ｍｎ、Ｂａ、Ｌａが挙げられる。アルミニウム金属元素の仕事函数４．２ｅＶよりも小さい仕事函数を有する元素の含有量は、各元素の固溶限界内の含有量が用いられる。なお、Ｓｉ元素の仕事函数はｎ型のシリコンの場合４．８５ｅＶである。
【００１１】
【作用】
Ａｌ金属にＳｉ元素を含有させると、導電性および生産性を損なうことなく、陰極に十分な耐酸化性が付与される。このＳｉ元素を添加したＡｌ合金に仕事関数の小さい金属元素を含有させると良好な電子注入性が得られる。
前記した陰極は沸点，蒸気圧の異なる少なくとも三つの元素を含有する組成物であるからフラッシュ蒸着法により陰極を形成するときに陰極組成の安定性と生産性が確保される。
【００１２】
【実施例】
本発明の実施例を図面に基づいて説明する。
図１は本発明の実施例に係る有機薄膜発光素子の一例を示す断面図である。
図２は本発明の実施例に係る有機薄膜発光素子の異なる例を示す断面図である。
【００１３】
図３は本発明の実施例に係る有機薄膜発光素子のさらに異なる例を示す断面図である。
図４は本発明の実施例に係る有機薄膜発光素子のさらに異なる例を示す断面図である。
上述の例において１は絶縁性透明基板、２は陽極、３は正孔注入層、４は発光層、５は電子注入層、６は陰極である。
【００１４】
絶縁性透明基板１は有機薄膜発光素子の支持体であり、ガラス、樹脂などが用いられる。
陽極２は金，ニッケル等の半透膜やインジウムスズ酸化物（ＩＴＯ）、酸化スズ（ＳｎＯ2 ）等の透明導電膜からなり、抵抗加熱蒸着，電子ビーム蒸着，スパッタ法等により形成される。膜厚は１０ないし５００ｎｍの厚さが好ましい。
【００１５】
正孔注入層３は発光層に効率よく正孔を輸送・注入し、該発光層４にて発光した光の波長領域においてできるだけ透明であることが望ましい。成膜方法としてはスピンコート，キャスティング，ＬＢ法，抵抗加熱蒸着，電子ビーム蒸着等があるが、抵抗加熱蒸着が一般的である。膜厚は５ないし５００ｎｍであり、好適には１０ないし８０ｎｍである。正孔注入物質としてはヒドラゾン化合物，ピラリゾン化合物，スチルベン化合物，アミン系化合物，等が用いられる。正孔注入物質の具体例が化学式（Ｉ―１）ないし化学式（Ｉ―７）に示される。
【００１６】
【化１】
【化２】
発光層４は正孔注入層３または陽極２より注入された正孔と、陰極６または電子注入層５から注入された電子により効率よく発光を行う。成膜方法としてはスピンコート，キャスティング，ＬＢ法，抵抗加熱蒸着，電子ビーム蒸着等があるが、抵抗加熱蒸着が一般的である。膜厚は５ないし５００ｎｍであり、好適には３０ないし８０ｎｍである。
【００１９】
発光層４としては金属キレート化合物，ペリノン誘導体，ジスチリルベンゼン誘導体等が用いられる。発光物質の具体例が化学式（II―１）ないし化学式（II―４）に示される。
【００２０】
【化３】
電子注入層５は電子を発光層４に効率よく輸送・注入することが必要である。成膜方法としてはスピンコート，キャスティング，ＬＢ法，抵抗加熱蒸着，電子ビーム蒸着等があるが、抵抗加熱蒸着が一般的である。膜厚は５ないし５００ｎｍであり、好適には３０ないし８０ｎｍである。
電子注入層５としてはオキサジアゾール誘導体，ペリレン誘導体等が用いられる。電子注入物質の具体例が化学式（III ―１）ないし化学式（III ―４）に示される。
【００２２】
【化４】
実施例１
膜厚１００ｎｍのインジウムスズ酸化物（ＩＴＯ）からなる陽極パターンを設けた５０ｍｍ角のガラスを基板とし、この基板を抵抗加熱蒸着装置内に戴置し、正孔注入層、発光層、陰極の順に成膜した。成膜に際して真空槽内は８×１０-4Ｐａまで減圧した。正孔注入層には化学式（Ｉ−２）に示される正孔注入物質を用い、ボート温度２３０℃で加熱し、成長速度を０．２ｎｍ／ｓとして６０ｎｍ厚さに成膜した。発光層には化学式（II―１）で示される発光物質を用い、ボート温度２７０℃で加熱し、成膜速度を０．２ｎｍ／ｓとして７０ｎｍ厚さに形成した。こののち基板を抵抗加熱蒸着装置から取り出すことなく、陰極パターン用ステンレスマスクを基板に取り付け、陰極としてＭｇＡｌＳｉワイヤー（組成比１：９８：１、線径１．０ｍｍ）を十分に加熱したタングステンボードに押しつけて３００ｎｍの膜厚にフラッシュ蒸着した。このフラッシュ蒸着により沸点，蒸気圧の異なる三つの元素が、ＭｇＡｌＳｉワイヤーと同一組成で同時且つ安定に発光層の上に蒸着される。
実施例２
膜厚１００ｎｍのインジウムスズ酸化物（ＩＴＯ）からなる陽極パターンを設けた５０ｍｍ角のガラスを基板とし、この基板を抵抗加熱蒸着装置内に戴置し、発光層、電子輸送層、陰極の順に成膜した。成膜に際して真空槽内は８×１０-4Ｐａまで減圧した。発光層には化学式（II−１）に示される発光物質を用い、ボート温度２７０℃で加熱し、成長速度を０．２ｎｍ／ｓとして６０ｎｍ厚さに形成した。電子輸送層には化学式（III −３）で示される電子輸送物質を用い、ボート温度２１０℃で加熱し、成膜速度を０．２ｎｍ／ｓとして４０ｎｍ厚さに形成した。こののち基板を抵抗加熱蒸着装置から取り出すことなく、陰極マスクパターン用ステンレスマスクを基板に取り付け、新たに抵抗加熱蒸着装置内に戴置し、陰極としてＭｇＡｌＳｉワイヤー（組成比１：９８：１、線径１．０ｍｍ）を十分に加熱したタングステンボードに押しつけて、３００ｎｍの膜厚にフラッシュ蒸着した。
比較例１
実施例１の陰極として二元蒸着法により、Ａｌ−Ｍｇ合金を３００ｎｍ厚さに成膜する他は実施例１と同様にして有機薄膜発光素子を形成した。
比較例２
実施例２の陰極として二元蒸着法により、Ａｌ−Ｍｇ合金を３００ｎｍ厚さに成膜する他は実施例２と同様にして有機薄膜発光素子を形成した。
【００２４】
このようにして得られた有機薄膜発光素子を連続試験し画質寿命および輝度半減期を測定した。ここで画質寿命は有機薄膜発光素子において、長径１００μｍ以上の非発光欠陥部（いわゆるダークスポット）が生成するまでの駆動時間を表す。測定結果を表１に示す。
【００２５】
【表１】
【００２６】
【発明の効果】
Ａｌを主成分とし、副成分としてＳｉ元素と、仕事関数の小さい元素を含有させた合金を陰極として用いると電子注入性あるいは導電性を損なうことなく、陰極の耐酸化性が向上し、特性と信頼性に優れる有機薄膜発光素子が得られる。
フラッシュ蒸着により陰極を製造するときは、沸点，蒸気圧の異なる元素を含む場合において元素組成の安定した陰極を効率良く製造することができる。
【図面の簡単な説明】
【図１】本発明の実施例に係る有機薄膜発光素子の一例を示す断面図
【図２】本発明の実施例に係る有機薄膜発光素子の異なる例を示す断面図
【図３】本発明の実施例に係る有機薄膜発光素子のさらに異なる例を示す断面図
【図４】本発明の実施例に係る有機薄膜発光素子のさらに異なる例を示す断面図
【符号の説明】
１ 絶縁性透明基板
２ 陽極
３ 正孔注入層
４ 発光層
５ 電子注入層
６ 陰極[0001]
[Industrial application fields]
The present invention relates to a cathode of an organic thin film light emitting element used as a light emitting source of various display devices and a method for manufacturing the same.
[0002]
[Prior art]
With the rapid increase in demand for flat panel displays that replace conventional cathode ray tubes, various display elements have been developed and put into practical use. Electroluminescence elements (hereinafter referred to as EL elements) are also in line with these needs, especially due to the fact that the entire element is made of solid, and because it emits light by itself, it has high resolution and high visibility not found in other displays. It attracts attention.
[0003]
What is currently put into practical use is an EL element mainly made of an inorganic material using a ZnS / Mn system for a light emitting layer. However, this type of inorganic EL element has a problem that the driving voltage required for light emission is as high as about 200 V, so that the driving method is complicated and the manufacturing cost is high. In addition, since the efficiency of blue light emission is low, it is difficult to achieve full color.
In contrast, thin-film light-emitting devices using organic materials can be greatly reduced in driving voltage required for light emission, and can be fully colored by adding various light-emitting materials. It has been broken.
[0004]
In particular, in a laminated type composed of an anode / hole injection layer / light emitting layer / cathode, tris (8-hydroxyquinoline) aluminum is used as the light emitting agent and 1,1-bis (4-N, N-di-acid is used as the hole injecting agent. Since it was reported that the use of (tolylaminophenyl) cyclohexane gave a luminance of 1000 cd / m 2 or more at an applied voltage of 10 V or less, development has been spurred (Appl. Phys. Lett. 51 , 913 (1987)).
[0005]
As described above, although thin film light emitting devices using organic materials strongly suggest the possibility of low voltage driving and full color, there are still many problems that must be solved in terms of performance. In particular, the problem of characteristic deterioration associated with long-time driving is a problem that must be overcome. One of the causes of the characteristic deterioration is insufficient cathode stability. The cathode material is preferably a metal having a small work function in order to improve the electron injection property, but has a problem that it is easily oxidized.
[0006]
[Problems to be solved by the invention]
In order to cope with this problem, the cathode is used as an alloy with a metal element having a high work function (Japanese Patent Laid-Open No. 2-15595), or a metal and alloy having a high work function on a metal or alloy having a low work function. A method of laminating (JP-A-4-233195) has been proposed. However, the former does not ensure electron injection properties unless it contains a large amount of a metal element (for example, Mg) having a low work function, so the composition ratio of the metal element (for example, Ag) having a large work function is small, and therefore the stability is not sufficient. The latter also has problems such as difficulty in preventing oxidation at the interface between the organic layer and the metal or alloy.
[0007]
The present invention has been made in view of the above points, and an object thereof is to provide an organic thin-film light-emitting element having excellent characteristics and reliability by developing a cathode having high electron injection property and excellent chemical stability, and a method for manufacturing the same. There is to do.
[0008]
[Means for Solving the Problems]
An object of the present invention is to provide an organic thin film light emitting device comprising an anode, a hole injection layer, an organic layer composed of a light emitting layer and an electron injection layer, and a cathode laminated on an insulating transparent substrate. In which the cathode contains aluminum as a main component, the silicon element as an accessory component , and an element selected from Mg, Ca , Mn, Ba, La whose work function is smaller than the work function of aluminum , and the content of silicon element There is achieved by 0.1 wt% to 3.00 wt% der Rukoto.
Also, in an organic thin film light emitting device in which an anode, an organic layer composed of at least a light emitting layer among a light emitting layer, an electron injecting layer, and a cathode are laminated on an insulating transparent substrate, the cathode is mainly composed of aluminum. And an element selected from Mg, C a , Mn, Ba, and La whose work function is smaller than that of aluminum as a subcomponent , and the content of silicon element is 0.1 to 3% by weight In the method for manufacturing an organic thin film light emitting device of 0.000% by weight, the cathode is achieved by forming a film by a flash vapor deposition method.
[0009]
The cathode of the organic thin film light emitting element is achieved by forming a film by flash vapor deposition.
The content of Al element in the cathode is preferably 90% by weight or more, more preferably 95% by weight or more.
The content of Si element in the cathode is preferably 0.01 to 3.00% by weight, more preferably 0.1 to 1.00% by weight.
[0010]
Examples of the element having a work function smaller than 4.2 eV of the aluminum metal element include Mg, Ca , Mn, Ba, and La from the viewpoint of economy. As the content of the element having a work function smaller than the work function of 4.2 eV of the aluminum metal element, the content within the solid solution limit of each element is used. Note that the work function of Si element is 4.85 eV in the case of n-type silicon.
[0011]
[Action]
When Si element is contained in Al metal, sufficient oxidation resistance is imparted to the cathode without impairing conductivity and productivity. When an Al alloy to which this Si element is added contains a metal element having a small work function, good electron injection properties can be obtained.
Since the cathode described above is a composition containing at least three elements having different boiling points and vapor pressures, the stability and productivity of the cathode composition are ensured when the cathode is formed by flash vapor deposition.
[0012]
【Example】
Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view showing an example of an organic thin film light emitting device according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view showing a different example of the organic thin film light emitting device according to the embodiment of the present invention.
[0013]
FIG. 3 is a sectional view showing still another example of the organic thin film light emitting device according to the embodiment of the present invention.
FIG. 4 is a sectional view showing still another example of the organic thin film light emitting device according to the embodiment of the present invention.
In the above example, 1 is an insulating transparent substrate, 2 is an anode, 3 is a hole injection layer, 4 is a light emitting layer, 5 is an electron injection layer, and 6 is a cathode.
[0014]
The insulating
The
[0015]
It is desirable that the hole injection layer 3 is as transparent as possible in the wavelength region of the light emitted from the
[0016]
[Chemical 1]
[Chemical formula 2]
The
[0019]
As the
[0020]
[Chemical 3]
The electron injection layer 5 needs to efficiently transport and inject electrons into the
As the electron injection layer 5, an oxadiazole derivative, a perylene derivative, or the like is used. Specific examples of the electron injecting substance are shown in chemical formula (III-1) to chemical formula (III-4).
[0022]
[Formula 4]
Example 1
A glass of 50 mm square provided with an anode pattern made of indium tin oxide (ITO) with a thickness of 100 nm is used as a substrate, this substrate is placed in a resistance heating vapor deposition apparatus, and a hole injection layer, a light emitting layer, and a cathode in this order. A film was formed. During film formation, the pressure in the vacuum chamber was reduced to 8 × 10 −4 Pa. For the hole injection layer, a hole injection material represented by the chemical formula (I-2) was used, heated at a boat temperature of 230 ° C., and grown to a thickness of 60 nm at a growth rate of 0.2 nm / s. A light emitting material represented by the chemical formula (II-1) was used for the light emitting layer, heated at a boat temperature of 270 ° C., and formed to a thickness of 70 nm at a film formation rate of 0.2 nm / s. After that, without removing the substrate from the resistance heating vapor deposition apparatus, a stainless steel mask for a cathode pattern was attached to the substrate, and a MgAlSi wire (composition ratio 1: 98: 1, wire diameter 1.0 mm) was sufficiently heated as a cathode on a tungsten board. It was pressed and flash evaporated to a film thickness of 300 nm. By this flash deposition, three elements having different boiling points and vapor pressures are deposited on the light emitting layer simultaneously and stably with the same composition as the MgAlSi wire.
Example 2
A glass of 50 mm square provided with an anode pattern made of indium tin oxide (ITO) with a thickness of 100 nm is used as a substrate, this substrate is placed in a resistance heating vapor deposition apparatus, and a light emitting layer, an electron transport layer, and a cathode are formed in this order. Filmed. During film formation, the pressure in the vacuum chamber was reduced to 8 × 10 −4 Pa. A light emitting material represented by the chemical formula (II-1) was used for the light emitting layer, heated at a boat temperature of 270 ° C., and formed to a thickness of 60 nm at a growth rate of 0.2 nm / s. For the electron transport layer, an electron transport material represented by the chemical formula (III-3) was used, heated at a boat temperature of 210 ° C., and formed to a thickness of 40 nm at a film formation rate of 0.2 nm / s. After that, without removing the substrate from the resistance heating vapor deposition apparatus, a stainless mask for the cathode mask pattern is attached to the substrate and newly placed in the resistance heating vapor deposition apparatus, and MgAlSi wire (composition ratio 1: 98: 1, wire) is used as the cathode. (1.0 mm in diameter) was pressed against a sufficiently heated tungsten board and flash evaporated to a film thickness of 300 nm.
Comparative Example 1
An organic thin-film light-emitting element was formed in the same manner as in Example 1 except that an Al—Mg alloy film was formed to a thickness of 300 nm by a binary vapor deposition method as the cathode of Example 1.
Comparative Example 2
An organic thin-film light-emitting element was formed in the same manner as in Example 2 except that an Al—Mg alloy film was formed to a thickness of 300 nm by a binary vapor deposition method as the cathode of Example 2.
[0024]
The organic thin film light-emitting device thus obtained was continuously tested to measure the image quality life and the luminance half-life. Here, the image quality life represents a driving time until a non-light emitting defect portion (so-called dark spot) having a major axis of 100 μm or more is generated in the organic thin film light emitting element. The measurement results are shown in Table 1.
[0025]
[Table 1]
[0026]
【The invention's effect】
When an alloy containing Si as a main component, Si element as an accessory component, and an element having a small work function is used as a cathode, the oxidation resistance of the cathode is improved without impairing the electron injecting property or conductivity. An organic thin film light emitting device having excellent reliability can be obtained.
When a cathode is manufactured by flash vapor deposition, a cathode having a stable element composition can be efficiently manufactured when elements having different boiling points and vapor pressures are included.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an example of an organic thin film light emitting device according to an embodiment of the present invention. FIG. 2 is a cross sectional view showing a different example of an organic thin film light emitting device according to an embodiment of the present invention. FIG. 4 is a cross-sectional view showing still another example of the organic thin film light emitting element according to the embodiment. FIG. 4 is a cross sectional view showing still another example of the organic thin film light emitting element according to the embodiment of the present invention.
1 Insulating
Claims (2)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13902195A JP3684614B2 (en) | 1995-06-06 | 1995-06-06 | Organic thin film light emitting device and method for manufacturing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13902195A JP3684614B2 (en) | 1995-06-06 | 1995-06-06 | Organic thin film light emitting device and method for manufacturing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08330072A JPH08330072A (en) | 1996-12-13 |
| JP3684614B2 true JP3684614B2 (en) | 2005-08-17 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13902195A Expired - Lifetime JP3684614B2 (en) | 1995-06-06 | 1995-06-06 | Organic thin film light emitting device and method for manufacturing the same |
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| Country | Link |
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| JP (1) | JP3684614B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7816863B2 (en) | 2003-09-12 | 2010-10-19 | Semiconductor Energy Laboratory Co., Ltd. | Light emitting device and method for manufacturing the same |
| JP2005108825A (en) * | 2003-09-12 | 2005-04-21 | Semiconductor Energy Lab Co Ltd | Light emitting apparatus and method of manufacturing the same |
| KR100611673B1 (en) * | 2005-01-31 | 2006-08-10 | 삼성에스디아이 주식회사 | Thin film formation method and manufacturing method of organic light emitting device |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05117845A (en) * | 1991-10-22 | 1993-05-14 | Matsushita Electric Ind Co Ltd | Device and method for film forming of compound material |
| JPH05159882A (en) * | 1991-12-04 | 1993-06-25 | Idemitsu Kosan Co Ltd | Manufacture of electron injectable electrode and manufacture of organic electroluminescence element therewith |
| JP3243311B2 (en) * | 1992-12-15 | 2002-01-07 | キヤノン株式会社 | EL device |
| JP2701738B2 (en) * | 1994-05-17 | 1998-01-21 | 日本電気株式会社 | Organic thin film EL device |
| JPH0896963A (en) * | 1994-09-28 | 1996-04-12 | Tdk Corp | Organic electroluminescent device |
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1995
- 1995-06-06 JP JP13902195A patent/JP3684614B2/en not_active Expired - Lifetime
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| Publication number | Publication date |
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| JPH08330072A (en) | 1996-12-13 |
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