1249368 九、發明說明·· 【發明所屬之技術領域】 本發明係有關有機光放射裝置（0LEDs)，卢其 ，用ΐ層發射層以產生白色光之白色有機光制装置。 【先前技術】 與非有機光放射裝置相比，由於 (OLEDs)係利用有機材料作為光發射層 : 射，所以該OLEDs乃磲亍_ «=*句自仃放 回岸速声P猶心 驅動電良好的 口應速度及夕種顏色的可能性 彩色顯示器時，其係可顯示出良好的顏 OLEDs係具有許多諸如單薄、緊湊及重 其乃適於作為攜帶式之資訊通訊顯示器。^等優點，所以 當使用放射白光之〇LEDs以實施 使用彩色滤光片以產生顏色。在這種狀況；；:夺單= 二可:預期幾個優點諸如次品率較 除；，一具有微細圖案之金屬罩幕被巧妙地移 且H 藍色（RGB)發射層75依讀沉積。 /、畚i光及紅光發射層之白光GLED具有如圖一所承 ㈣=陽極1被沉積在—基板上，而—電洞傳輸與蘇 射層10 ’―電洞阻播與紅光發射層η，—電子傳輸 層12及一陰極9則係被依次沉積在該陽極1之上。還 可能將一電洞傳輸與藍光發射層13 , 一紅光發射層14， -電，且擋層15’ 一電子傳輸層16及一陰極9依:欠沉積 於該陽極1之上，以獲得白色光發射。 1249368 以上提到的兩種結構都具有相同的驅動原理，下文將 加以說明。 、 當在該陽極1與該陰極9之間施加一驅動電壓時，藉 由電洞傳輸層1〇與13，從該陽極〗注入的電洞乃傳輸至 該紅光發射層U與Η。此時，具有最高填滿分子軌域 (HOMO)之電洞阻擋層15乃阻擋該電洞’使其無法到達該 陰極9。 同時，電子乃自該陰極9通過該電子傳輸層12與16, 注入該紅光發射層u與14，而且，當載體在界面及該 電洞傳輸層1G與13及該紅光發射層_ 14的大部分地 方與該電洞重新結合時，其乃會產生激子。當該產生的激 子躍遷至平衡狀恶時就會發出光。也就是說，該電洞傳輸 層10與13發出藍光，而該紅光發射層u與14則發出紅 光’進而由該兩種顏色的光產生白光。 在以上述方式操作之有機光放射裝置（0LED)中，由 於歧激子的分布難以控制，而且該激子的分布係隨施加電 £而快速雙化，因此很難控制白光之純度。此外，因為該 白光係僅由兩種光組成，即僅由該電洞傳輸層1〇與13所 產生激子發射的藍光與由該紅光發射層u與14所產生激 子發射的紅光組成，因而其產生白光的效率較低。即使用 形色濾光片，其亦很難應用於彩色顯示器裝置，因為其所 產生之白光中係還包括一點點綠光。 圖二示意了一種帶有三層發射層之傳統白光0LED的 能階圖。陽極1係、沉積於最底層，—電洞傳輸層18，一 1249368 藍光發射層19，一綠光發射層20，及一紅光發射層21依 次沉積於該陽極1之上，然後其上又沉積一電子傳輸層 22與一陰極9。 具有上述結構之OLED係依照下述原理產生白光。 當在該陽極1及該陰極9之間外加一電壓時，電洞與 電子係分別自該陽極1與該陰極9注入。該注入之電洞與 電子係分別通過該電洞傳輸層18與該電子傳輸層22，而 在該三層光發射層19、20和21内產生激子。該產生之激 子在該三層光發射層19、20和21任意分布，並躍遷至平 衡狀態以放射光。 然而，以上述方式操作之OLED，亦由於不易控制放 射該紅綠藍光之激子數量，而難以調節白光之純度，並且 光之發射效率低。此外，還存在結構限制問題，即從能階 觀點來說，該藍光發射層係必須較該綠光發射層20與該 紅光發射層21更靠近該陽極1方可。 【發明内容】 本發明之技術主題係解決上述習知技術之缺點及困 難，並提供一種白色有機光放射裝置，該裝置能夠均勻地 放射出紅光、綠光和藍光，以高效率地產生白光。 為了解決這些問題，本發明提供了一種具有白光平衡 層及激子限制結構之OLED。 詳細地說，本發明提供了一種有機光放射裝置，其包 括一陽極；一形成於該陽極上之電洞注入層；一形成於該 電洞注入層上之電洞傳輸層；形成於該電洞傳輸層上之數 1249368 層光發射層；在該數層光發射層之兩預定層之間所形成並 具有一電子阻擔效應之至少一有機材料層·，一形成於該光 發射層上之電子傳輸層；及一形成於該電子傳輸層上之陰 極0 該數光發射層之至少一層，與其鄰近兩侧之兩層相 比，應具有較低能階為佳以形成一激子限制結構。 在該數層光發射層之中，最好包括一綠光發射層，一 紅光發射層，及一藍光發射層，而且該綠光發射層係位於 該電洞傳輸層與該紅光發射層之間，以形成一激子限制結 構。在該數層光發射層之中，最好包括一綠光發射層，一 紅光發射層，及一藍光發射層，而且在該紅光發射層與該 藍光發射層之間，至少形成一層具有電子阻擋效應之有機 材料層。 該電洞傳輸層，該數層光發射層及該電子傳輸層中之 至少一層係包括一 0. 1至5. Owt· % (重量百分比）之摻雜 劑。該摻雜劑包括至少以下物質之一種：香豆素6，紅熒 烯，4-（二氰基亞曱基）-2-甲基-6- (P-二甲基氨基苯乙 烯基）-4H-嗶喃DCM)，4-(二氰曱烯基）-2-1-叔丁基-6-(1，1，7，7-四曱基久洛尼定基-9-稀快基）-4H- σ畢喃 (DCJTB)，二萘嵌苯，喹吖啶酮，DCM2,2,3,7,8, 12, 13, 17, 18-八乙基-21H，23H-外吩鉑（PtOEP)，及銥（瓜）雙[(4, 6-二氟苯基）-吡啶-N，C2’ ]嗶啶甲酸鹽（Firpic)，其中PtOEP 與Firpic係鱗光性摻雜劑。 綠光發射層，紅光發射層及藍光發射層，其厚度範圍 1249368 分別為100A至500A之間。該綠光發射層包括三（8—經基 啥琳）銘為主體材料；該紅光發射層至少包括下述之一種 為主體材料，即[N，N，-雙（萘-1-基）苯基]-N，N，—雙（苯基） 聯苯二胺（NPB)及4, 4’ -雙（σ卡峻-9-基）聯苯（CBP)中之一 種為主體材料，這兩種材料均為鱗光性基質材料；藍光發 射層至少包括下述之一種為主體材料，即4, 4,-雙（2, 2-一苯-乙晞-1-基）-聯苯（DPVBi)，4, 4”-雙（2, 2-二苯乙烯 -1-基）-p-叔基苯撐（DPVTP)及螺旋形-DPVBi為主體材 電洞注入層的厚度為400A至1500A，而該電洞傳輸 層的厚度為10 0 A至5 0 0 A。該電洞注入層與該電洞傳輸層 至少包括以下之一種為主體材料，即4, 4’，4，，-三[N-3-曱 基苯基-N-苯基-氨基]-三苯胺（m-MTDATA)及Ν，Ν’ -雙（萘 -1-基）-Ν，Ν’ -雙（苯基）聯苯二胺（ΝΡΒ)中之至少一種為主 體材料。 該電子傳輸層厚度在100Α至1，000Α之間。 具有電子阻擋效應之有機材料層，至少其中之一層厚 度在10Α至30Α之間。具有電子阻擋效應之有機材料層， 至少其中之一層包括Ν，Ν’ -二萘基-1-Ν，Ν’ -二苯基聯笨二 胺（NPB)(=a-NPD)為主體材料。 該陽極厚度在1，000Α至2,000Α之間，由氧化銦錫 (I 丁0)，二氧化錫Sn〇2與氧化鋅ΖηΟ之至少一種組成。 該陰極厚度在500Α至5, 000Α之間，至少由Li，LiF， Mg，Al，Al-Li，Ca，Mg-In 與 Mg-Ag 中之一種組成。 1249368 該陰極可以具備雙層結構，包括一厚度在5A至20A 之間的LiF層及厚度在1，000A至2,000A之間的A1層。 該多層光發射層可能包括一綠光發射層，一紅光發身于 層，及一藍光發射層，此外還可包含一發射增強層，以提 高該藍光發射層與該電子傳輸層間的發射效率，該發射增 強層包括一藍光發射層，以及一 η-型層與一 p-型層中之 至少一層。 本發明提供一有機光放射裝置，該裝置包含一陽極； 一形成於該陽極上之電洞注入層；一形成於該電洞注入層 上之電洞傳輸層；形成於該電洞傳輸層上之多層光發射 層；一形成於該光發射層上之電子傳輸層；及一形成於該 電子傳輸層上之陰極。其中該多層光發射層中之至少一層 與其鄰近兩側形成一激子阻擂結構之兩層相比，係具有較 低能級。 此外，該裝置還可包括至少一層具備電子阻擋效應且 插入在該多層光發射層之兩層預先確定層間之有機材料 層。 【實施方式】 本發明將參照附圖，在下文中更充分地加以說明。在 附圖中係顯示了本發明之最佳實施例。這些實施例僅作為 說明之範例，本發明不受其限制。 圖三Α係顯示依據本發明一實施例白色OLED之一層 結構剖面圖。圖三B係顯示依據本發明一實施例白色OLED 之能階結構圖。 1249368 如圖二A所示，依據本發明之一實施例，該白色〇lEd 係包括一絕緣基板1〇0和依次沉積在該絕緣基板丨㈧之上 一陽極1、一電洞注入層2、一電洞傳輸層3、一綠光發 射層4、一紅光發射層5、一白光平衡層6、一藍光發射 層7、一電子傳輸層8，以及一陰極9。 在此結構中，藉由控制插在該藍光發射層7與紅光發 射層5間之該白光平衡層6的厚度，從而控制紅光、綠光 與藍光之發射比率。該白光平衡層6有效地阻擔了藉由該 陰極9、該電子傳輸層8以及該藍光發射層7所導入電子 之運動，以控制紅光、綠光與藍光之發射比率。 因為該綠光發射層之LUM〇 (最低空的分子軌域）較 分別鄰近其兩側之該電洞傳輸層3與紅光發射層5要低， 乃形成一激子限制結構17,從而提高了該綠光發射效率。 在該實施例中，該電洞傳輸層3、該發射層4、5、7 及該電子傳輸層8之至少-層或多層係包括摻雜劑，俾使 該等層4、5及7藉由電洞—電子結合以發光。可使用香豆 素6，紅熒烯，4-（二氰基亞甲基）—2-曱基一6— (p一二曱 基氨基笨乙烯基）—4H-嗶喃（DCM)，或4-,(二氰甲烯基） -2-1-叔丁基一6— (M，7,7一四甲基久洛尼定基一9一烯炔 基）-4H-嗶喃（DCJTB)作為摻雜劑。為了產生藍光，二萘 嵌苯，喹吖啶酮，或DCM2亦可用作摻雜劑。 作為一種磷光摻雜劑，2, 3, 7, 8, 12, 13, 17, 18-八乙基 - 21H或23H-卟吩鉑（Pt0EP)可用於紅光，銥（瓜）雙 [(4, 6-二氟苯基）—吡啶—N，C2,]嗶啶曱酸鹽（^印^)等可 1249368 用於藍光。摻雜劑含量係該電洞傳輸層3、該發射層4、5、 7及該電子傳輸層8之基質材料的1〜20wt.% (重量百分 含量）。上述摻雜物係具有以下之化學式。1249368 IX. INSTRUCTION DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an organic light emitting device (OLEDs), a white organic light device using a germanium emitting layer to generate white light. [Prior Art] Compared with non-organic light-emitting devices, since (OLEDs) use organic materials as light-emitting layers: the OLEDs are 磲亍_ «=* sentences from the 回 回 回 速 速 犹 犹 犹 犹The good quality of the port and the color of the color of the color display, it can show that good color OLEDs have many such as thin, compact and heavy, which is suitable as a portable information communication display. ^ and so on, so when using LEDs that emit white light to implement the use of color filters to produce color. In this case;;: ordering = two can: several advantages are expected such as the defective rate; a metal mask with a fine pattern is subtly moved and the H blue (RGB) emitting layer 75 is deposited. . /, 畚i light and red light emitting layer of white light GLED has the same as shown in Figure 1 (4) = anode 1 is deposited on the substrate, and - hole transmission and the shot layer 10 '- hole blocking and red light emission The layer η, the electron transport layer 12 and a cathode 9, are sequentially deposited on the anode 1. It is also possible to transmit a hole to the blue light emitting layer 13, a red light emitting layer 14, - and the barrier layer 15', an electron transport layer 16 and a cathode 9 are deposited on the anode 1 to obtain White light emission. 1249368 Both of the above mentioned structures have the same drive principle, as explained below. When a driving voltage is applied between the anode 1 and the cathode 9, the holes injected from the anode are transferred to the red light emitting layers U and 借 by the hole transport layers 1 and 13. At this time, the hole barrier layer 15 having the highest filled sub-track domain (HOMO) blocks the hole 'from reaching the cathode 9. At the same time, electrons are injected from the cathode 9 through the electron transport layers 12 and 16, and the red light emitting layers u and 14 are implanted, and when the carrier is at the interface and the hole transport layers 1G and 13 and the red light emitting layer _ 14 Most of the place, when recombined with the hole, produces excitons. Light is emitted when the generated excitons transition to equilibrium. That is, the hole transport layers 10 and 13 emit blue light, and the red light emitting layers u and 14 emit red light' to generate white light from the two colors of light. In the organic light emitting device (OLED) operated in the above manner, since the distribution of the exciton is difficult to control, and the distribution of the excitons is rapidly doubled with the application of electric charge, it is difficult to control the purity of white light. In addition, since the white light system is composed only of two kinds of light, that is, blue light emitted only by excitons generated by the hole transport layers 1 and 13 and red light emitted by excitons generated by the red light emitting layers u and 14 Composition, and thus its efficiency in producing white light is low. Even if a color filter is used, it is also difficult to apply to a color display device because the white light generated therein also includes a little green light. Figure 2 illustrates an energy level diagram of a conventional white OLED with three layers of emissive layers. An anode 1 is deposited on the bottom layer, a hole transport layer 18, a 1249368 blue light emitting layer 19, a green light emitting layer 20, and a red light emitting layer 21 are sequentially deposited on the anode 1, and then thereon An electron transport layer 22 and a cathode 9 are deposited. The OLED having the above structure produces white light in accordance with the following principle. When a voltage is applied between the anode 1 and the cathode 9, a hole and an electron system are injected from the anode 1 and the cathode 9, respectively. The injected holes and electrons pass through the hole transport layer 18 and the electron transport layer 22, respectively, and excitons are generated in the three light-emitting layers 19, 20 and 21. The generated excitons are arbitrarily distributed in the three-layer light-emitting layers 19, 20 and 21, and are transitioned to a balanced state to emit light. However, the OLED operated in the above manner also has difficulty in controlling the purity of white light due to the difficulty in controlling the number of excitons that emit the red, green and blue light, and the light emission efficiency is low. Further, there is a problem of structural limitation that the blue light emitting layer must be closer to the anode 1 than the green light emitting layer 20 and the red light emitting layer 21 from the energy level viewpoint. SUMMARY OF THE INVENTION The technical subject of the present invention solves the above-mentioned drawbacks and difficulties of the prior art, and provides a white organic light emitting device capable of uniformly emitting red light, green light, and blue light to efficiently generate white light. . In order to solve these problems, the present invention provides an OLED having a white light balance layer and an exciton confinement structure. In detail, the present invention provides an organic light emitting device including an anode, a hole injection layer formed on the anode, and a hole transport layer formed on the hole injection layer; a number of 1249368 layers of light-emitting layers on the hole transport layer; at least one organic material layer formed between the two predetermined layers of the plurality of light-emitting layers and having an electron-resistance effect, one formed on the light-emitting layer And an electron transport layer; and a cathode formed on the electron transport layer. The at least one layer of the plurality of light emitting layers should have a lower energy level to form an exciton limit than the two layers adjacent to the two sides. structure. Preferably, the plurality of light emitting layers comprise a green light emitting layer, a red light emitting layer, and a blue light emitting layer, and the green light emitting layer is located in the hole transport layer and the red light emitting layer. Between to form an exciton-limiting structure. Preferably, the plurality of light emitting layers comprise a green light emitting layer, a red light emitting layer, and a blue light emitting layer, and at least one layer is formed between the red light emitting layer and the blue light emitting layer. An organic material layer with an electron blocking effect. The O. 5% to 5% by weight of the dopant. The dopant comprises at least one of the following: coumarin 6, rubrene, 4-(dicyanoindenyl)-2-methyl-6-(P-dimethylaminostyryl)- 4H-anthracene DCM), 4-(dicyanodecenyl)-2-1-tert-butyl-6-(1,1,7,7-tetradecyl-julolidine-9-carboyl) -4H- σBiran (DCJTB), perylene, quinacridone, DCM 2,2,3,7,8, 12, 13, 17, 18-octaethyl-21H, 23H-external phenylplatinum PtOEP), and bismuth (melon) bis[(4,6-difluorophenyl)-pyridine-N,C2'] acridine formate (Firpic), in which PtOEP and Firpic are scaly dopants. The green light emitting layer, the red light emitting layer and the blue light emitting layer have a thickness range of 1249368 between 100A and 500A. The green light emitting layer comprises three (8-by-base) as the host material; the red light emitting layer comprises at least one of the following materials, namely [N, N, -bis(naphthalen-1-yl) One of phenyl]-N,N,-bis(phenyl)biphenyldiamine (NPB) and 4,4'-bis(σKang-9-yl)biphenyl (CBP) is the host material. Both materials are scaly matrix materials; the blue emission layer includes at least one of the following materials, namely 4, 4,-bis(2,2-monophenyl-ethin-1-yl)-biphenyl ( DPVBi), 4, 4"-bis(2,2-distyryl-1-yl)-p-tert-phenylene (DPVTP) and spiral-DPVBi are the main body hole injection layer thickness of 400A to 1500A The hole transport layer has a thickness of 100 A to 500 A. The hole injection layer and the hole transport layer include at least one of the following materials, namely 4, 4', 4, and -3 [N-3-decylphenyl-N-phenyl-amino]-triphenylamine (m-MTDATA) and hydrazine, Ν'-bis(naphthalen-1-yl)-fluorene, Ν'-bis(phenyl) At least one of biphenyldiamine (yttrium) is a host material. The electron transport layer has a thickness of between 100 Å and 1,000 Å. An organic material layer having an electron blocking effect, at least one of which has a thickness between 10 Å and 30 Å. An organic material layer having an electron blocking effect, at least one of which includes Ν, Ν'-dinaphthyl-1-anthracene, Ν' - Diphenyl phenyldiamine (NPB) (= a-NPD) as the host material. The thickness of the anode is between 1,000 Å and 2,000 Å, which is composed of indium tin oxide (I butyl 0), tin dioxide Sn 〇 2 And at least one composition of zinc oxide ΖηΟ. The cathode has a thickness of between 500 Å and 5,000 Å, and is composed of at least one of Li, LiF, Mg, Al, Al-Li, Ca, Mg-In and Mg-Ag. The cathode may have a two-layer structure including a LiF layer having a thickness between 5A and 20A and an A1 layer having a thickness between 1,000A and 2,000A. The multilayer light-emitting layer may include a green light-emitting layer, a red The light is emitted from the layer, and a blue light emitting layer, and further includes an emission enhancement layer for improving the emission efficiency between the blue light emitting layer and the electron transport layer, the emission enhancement layer including a blue light emitting layer, and a η- At least one of a type layer and a p-type layer. The present invention provides an organic light emission a device comprising: an anode; a hole injection layer formed on the anode; a hole transport layer formed on the hole injection layer; and a plurality of light-emitting layers formed on the hole transport layer; An electron transport layer formed on the light emitting layer; and a cathode formed on the electron transport layer, wherein at least one of the plurality of light emitting layers is compared with two layers of an exciton blocking structure formed on both sides thereof , has a lower energy level. Furthermore, the apparatus may further comprise at least one layer of an organic material having an electron blocking effect and interposed between the two predetermined layers of the multilayer light-emitting layer. [Embodiment] The present invention will be described more fully hereinafter with reference to the accompanying drawings. The preferred embodiment of the invention is shown in the drawings. These examples are merely illustrative and the invention is not limited thereto. Figure 3 is a cross-sectional view showing a layer structure of a white OLED according to an embodiment of the present invention. Figure 3B is a diagram showing the energy level structure of a white OLED according to an embodiment of the present invention. 1249368 As shown in FIG. 2A, according to an embodiment of the present invention, the white 〇1Ed includes an insulating substrate 〇0 and an anode 1 and a hole injection layer 2 which are sequentially deposited on the insulating substrate 八 (8). A hole transport layer 3, a green light emitting layer 4, a red light emitting layer 5, a white light balancing layer 6, a blue light emitting layer 7, an electron transport layer 8, and a cathode 9. In this structure, the emission ratio of red light, green light and blue light is controlled by controlling the thickness of the white light balance layer 6 interposed between the blue light-emitting layer 7 and the red light-emitting layer 5. The white light balancing layer 6 effectively blocks the movement of electrons introduced by the cathode 9, the electron transport layer 8, and the blue light emitting layer 7 to control the emission ratio of red light, green light and blue light. Since the LUM〇 (lowest empty molecular orbital domain) of the green light emitting layer is lower than the hole transporting layer 3 and the red light emitting layer 5 adjacent to the two sides thereof, an exciton confinement structure 17 is formed, thereby improving The green light emission efficiency. In this embodiment, at least the layer or layers of the hole transport layer 3, the emissive layers 4, 5, 7 and the electron transport layer 8 comprise dopants, such that the layers 4, 5 and 7 are borrowed. It is combined by a hole-electron to emit light. Can use coumarin 6, rubrene, 4-(dicyanomethylidene)-2-mercapto-6-(p-didecylamino stupidyl)-4H-furan (DCM), or 4-, (Dicyanomethyl)-2-1-tert-butyl-6-(M,7,7-tetramethyl-julonidine- 9-enynyl)-4H-purine (DCJTB) As a dopant. In order to produce blue light, perylene, quinacridone, or DCM2 can also be used as a dopant. As a phosphorescent dopant, 2, 3, 7, 8, 12, 13, 17, 18-octaethyl- 21H or 23H-porphine platinum (Pt0EP) can be used for red light, sputum (melon) double [(4 , 6-difluorophenyl)-pyridine-N, C2,] acridine citrate (^, ^) can be used for blue light. The dopant content is 1 to 20 wt.% (weight percent) of the hole transport layer 3, the emissive layers 4, 5, 7 and the matrix material of the electron transport layer 8. The above dopant system has the following chemical formula.
Rrpie 12 1249368Rrpie 12 1249368
CBPCBP
形成該發射層4、5及7之基質材料如下。該綠光發 :層4之基質材料係三（8_羥基喹啉）鋁。該紅光與/或 黃光發射層5之基質材料係磷光性基質材料[N，N，_雙（萘 +基）苯基]-N，N，-雙（苯基）聯苯二胺（㈣）及4,4，_雙 (味唾_9_基）聯苯（CBp)中之一種。該藍光發射層7之基質 材料係4, 4 -雙（2, 2-二苯-乙烯-1_基）_聯苯（DpvBi)。 低分子材料之4, 4"-雙（2, 2-二笨乙烯—丨-基）—^叔基 # 苯撐（DPVTP)與螺旋-DPVBi等也可用作該藍光發射層7之 基質材料。The matrix materials forming the emissive layers 4, 5 and 7 are as follows. The green light: the matrix material of layer 4 is tris(8-hydroxyquinoline)aluminum. The matrix material of the red and/or yellow light emitting layer 5 is a phosphorescent host material [N,N,_bis(naphthalenyl)phenyl]-N,N,-bis(phenyl)biphenylenediamine ( (4)) and 4, 4, _ double (taste -9) phenyl (CBp). The matrix material of the blue light-emitting layer 7 is 4,4-bis(2,2-diphenyl-ethene-1_yl)-biphenyl (DpvBi). 4, 4"-bis(2,2-di-p-ethylene-fluorenyl-yl)--tert-group #phenylene (DPVTP) and helix-DPVBi, etc., which are also used as the matrix material of the blue light-emitting layer 7 .
為了提高效率並協調顏色，該等發射層4、5及7係 13 1249368 藉由添加上述摻雜劑材料而形成。 该發射層4、5及7 ，而且該厚度範園可 根據對產生白光之貢獻度大小，售 的厚度最好在100A至200A之間為宜， 根據所用材料之特性而變化。 適用於該電洞注入層2與該電洞傳輸層3之材料係帶 有具備電洞傳輸特性之三苯基胺基團。如4 二In order to improve efficiency and coordinate color, the emissive layers 4, 5 and 7 13 1249368 are formed by adding the above dopant material. The emissive layers 4, 5 and 7 and the thickness of the thickness may preferably be between 100 A and 200 A depending on the contribution to the white light generation, depending on the characteristics of the materials used. The material suitable for the hole injection layer 2 and the hole transport layer 3 is provided with a triphenylamine group having a hole transporting property. Such as 4 two
、Ν，Ν，- 雙（萘-1-基）-Ν，Ν’ - 雙（苯基）聯苯二胺（ΝΡβ)等即可被用 [N-3 - 述化學式。, Ν, Ν, - bis(naphthalen-1-yl)-oxime, Ν'-bis(phenyl)biphenyldiamine (ΝΡβ), etc. can be used [N-3 - the chemical formula.
於該電洞注入層2與該電洞傳輸層3。上述材料係具有下 形成於該陽極1上之該電洞注入層2，其厚度係以在 400A至1，500A之間者為佳；該電洞傳輸層3，其厚度係 以在100A至500A之間者為佳。 在本實施例中，該OLED係包括通常被用作為典型 OLED的絕緣基板1〇〇。實質上，該基板以具有良好透明 性，非常平整表面，易於處理，及良好防水性能之玻璃基 板或透明塑料基板為佳。 該陽極1係由具優異透明性及導電性之材料所組 成，諸如氧化銦錫（ITO)，Sn〇2，ZnO等，使具有在1，oqqa 至2, 000A間之厚度。 1249368 該陰極9係由金屬組成，諸如Li，Mg，A1，M-Li Ca Mg-In，Mg-Ag等，使具有在i _A至2，刚A間之厚^ 此處，該陰極9最好由具有高活性、低功功能且厚又度 在5,00A i 5,000A間之銘層所組成。此雙層結構對該装 置之穩定性與效率較為適宜。 、 該電子傳輸層8係由-電子傳輸層材料如三（8_經基 喹琳）鋁（Alq3)所組成，使具有在而至間^ 度。 該白光平衡層6係由[N，N，-雙（萘-卜基）苯 基]-N，N -雙（苯基）聯苯二胺（NpB)(=a—NpD)所組成，使 具有在10A至30A間之厚度。 圖二B係依據本發明一實施例中白色〇LED之能階結 構圖。 … 該具有電子阻擋效應之白光平衡層6係被插在該紅 光發射層5與該藍光發射層7之間；而該具低LUM〇 (最 低空的分子執域）級之綠光發射層4則係被插在該電洞傳 輸層3與該紅光發射層5之間，以形成一量子井，即該激 子限制結構17。 在此結構中，根據產生白光之貢獻度，該白光平衡層 6之希望厚度係在ι〇Α至30A之間。藉由調節該白光平衡 層6之厚度，就可以控制到達該紅光發射層5與該綠光發 射層4的電子數量，以及控制由於該能量壁而積聚在該白 光平衡層6界面的電子數量。 為了形成該激子限制結構17，該綠光發射層4係必 15 1249368 須插在該電洞傳輸層3與該紅光發射層5之間，以形成一 良好形狀之能階結構。 如上所述，依照本發明一實施例之白色OLED係具有 按下述順序依次沉積冬結構：陽極、電洞注入層、電洞傳 輸層、綠光發射層、紅光發射層、白光平衡層、藍光發射 層、電子傳輸層與陰極。其中該紅光發射層可由一黃光發 射層所代替。 依照能階或所用基質材料的安排，在依次積聚之有機 層中，該紅光或黃光發射層5與該白光平衡層6的位置係 可以交換的。例如，如圖四所示，該裝置可按以下順序形 成：陽極，電洞注入層，電洞傳輸層，綠光發射層，白光 平衡層，紅光發射層，藍光發射層，電子傳輸層及陰極。 如圖五所示，為了獲得高效白色OLED，該裝置還可 包括一位於該藍光發射層7與該電子傳輸層8間之發射增 強層23，以提高該藍光發射層7之發射效率。該發射增 強層23係具有多層結構，諸如藍光發射層/η-型層、藍光 發射層/ρ-型層、及藍光發射層/η型層/ρ型層。 在本發明實施例之白色OLED中，由於在該裝置運轉 期間產生的激子係根據該紅光發射層5、綠光發射層4、 及藍光發射層7的每一貢獻度來控制使其進行適當分 配，進而藉由該白光平衡層6以產生白光。因此，無需特 別依賴於該紅光、綠光與藍光層之結構，諸如該摻雜劑的 濃度及該等發射層的厚度，就可獲得每種顏色的最大發射 效率。 16 1249368 參閱圖一，經由該電洞阻擋層10與15之電洞阻擋效 應，一傳統白色OLED係藉著該電洞傳輪層1〇及13與該 發射層11及14之集層中及其界面上所引導的光發射，從 而產生白光。然而，在本發明中，該白光平衡層6係藉由 該電子阻擋效應控制該電子分配，從而使在該藍光發射層 7中未被使用之激子’可以貞獻給該紅光發射層5與該綠 光發射層4。 在使用如圖一所示電洞阻擋層（HBL)材料的情況下， 為了滿足在此階方面的發射機構，某種結構局限性係無法 避免的。例如，該藍光發射層1〇肖13必須被沉積在較該 紅光，射層U、14和21更接近該陽極1。然而，.依照本 發明貫施例之白色OLED就無此限制。 而且，藉著摻雜對有機光裝置的使用壽命有相當大$ 響的電洞傳輸層5,就可以藉著能量在主體盥客體間之： 遞:解決諸如當該電洞傳輸層5被暴露至制子時該^ 置命命之縮短及所產生降解等問題。 人們之！"子阻擔結構17係用於解決在_領域中 前時，問題’即當㈣光發射層4被沉積在該陽極1 綠和幻之rr 均衡三種均衡光（紅、 子阻紐嶋㈣係可獲得該 並受到限制。因二之激子乃被發 °亥，，、彔先㈣之&低錄問題就得到 17 1249368 解決。該問題不但是使用發射裝置之HBL的一個典型問 題；亦是藉由三層發射層獲得白光之白色OLED的典型問 題。而且，藉由上述量子井結構，因為藍光與紅光發射未 使用之過剩激子係僅參與綠光發射，所以其對阻止無光發 射時對該陽極1做出貢獻係有益的。該陽極1即係該裝置 使用壽命縮短的一個原因。 下文將詳細說明本發明幾個較佳實施例，其中將涉及 各層之厚度及材等問題。 下述實施例係為了有助於理解本發明而提供的，本發 明並不侷限於這些實施例。 下文實施例將以圖三中之參考數字進行說明。 [第一實施例] ITO (氧化銦錫）係沉積於一玻璃基板100上，以形 成一具有厚度為1800A之陽極1。在該ITO塗層之基板100 上，藉真空沉積法沉積m-MTDTA，以形成一具有厚度為 400A之電洞注入層2。 在該電洞注入層2之上，藉真空沉積NPB，以形成一 厚度為100A之電洞傳輸層3。 在該電洞傳輸層3之上，藉由真空沉積Αίφ與香豆 素6，形成一厚度為180Α之綠光發射層4。在此步驟中， 該兩種材料係同時被沉積，該綠光發射層4中係含有 99wt· %的Alq3和lwt. %的香豆素6。 緊接著，藉著真空沉積NPB和DCM，形成一厚120A 之紅光發射層5。NPB和DCM係以與該綠光發射層4相同 18 1249368 的方式同時沉積。在此處，該紅光發射層5中係含有 96wt. %的 NPB 和 4. Owt. %的 DCM。 在該紅光發射層5上，藉由NPB真空沉積，形成一能 夠控制該激子分布的白光平衡層6，該白光平衡層6係具 有厚度17A。 接下來，藉由真空沉積DPVBi，在該白光平衡層6之 上形成一藍光發射層7,並藉由真空沉積Alq3，在該藍光 發射層7之上形成一電子傳輸層8。該藍光發射層7係具 有厚度180A，而該電子傳輸層8則具有厚度120A。 緊接著，在該電子傳輸層8之上沉積一厚度為10A之 LiF電子注入層。然後在該LiF層之上沉積一厚度為 2, 000A的A1層，以形成一陰極9。 在得到的0LED中，藉由在該紅光發射層5及該藍光 發射層7間所形成之白光平衡層6，係可望產生該電子阻 擋效應。由於此效應，一部分電子對摻雜DPVBi之藍光發 射層7的光發射做出貢獻，另一部分電子對摻雜DCM之紅 光發射層5貢獻橘紅光之發射，而其它部分電子則對摻雜 香豆素之綠光發射層4貢獻綠光之發射。 圖六顯示依據本發明第一實施例白光0LED之光發射 光譜、色坐標及效率特性。 在圖六之發射光譜中，很容易就可看出紅、綠和藍光 係均勻地對產生白光做出貢獻，它們的波峰分別位於455 nm，510 nm和590 nm附近。此時，所發出之白光其色坐 標位置為（0· 33，0· 38)，而發光效率則為6. lcd/A， 19 1249368 2.31m/W〇 [第二實施例] 該第二實施例與該第一實施例相比，該第二實施例係 具有下述兩個與該第一實施例迥異之特性。NPB與紅熒烯 係在真空下同時沉積形成該紅光發射層5，該紅光發射層 5含有97wt. %的NPB和3wt. %的紅熒稀。該白光平衡層6 係具有厚度19A，以協調顏色之純度。 結果，在該第二實施例中，一部分激子對該紅光發射 層5之紅熒烯貢獻黃橘色光發射，另一部分激子對藍光與 綠光發射做出貢獻，使藉由控制該白光平衡層6之厚度變 化協調顏色之純度。 圖七顯示依據本發明第二實施例白光OLED之光發射 光譜、色坐標及效率特性。 參照圖七之發射光譜，紅、綠和藍全部三種顏色係對 白光發射都做出貢獻，每種顏色係分別具有最大波長峰 455 nm，511 nm及560 nm。在此種情況下，所發出之白 光係具有色坐標位置為（0.28，0.36)，而發光效率則為 6· 8cd/A，2·51m/W。 [第三實施例] 第三實施例與第二實施例係方法相同，但是在該第三 實施例中，所形成的該白光平衡層6之厚度係為17A。 如上所述，該白光平衡層6係控制影響光發射之電子 分佈。也就是說，該白光平衡層6控制該激子之分布。例 如，如果形成於該紅光發射層5和該藍光發射層7間之該 20 1249368 —W 9 6的厚度減小，由於該電子阻擔效應之減少， «光發射層7對白光發射之貢獻乃減少，而該綠光發射 層4與該、红光發射層5對白光發射之貢獻則增加。因為該 表光$ 光之貝獻增加，所以該白光之色坐標位置乃向長 波長位置移動。 圖八顯不依據本發明第三實施例白光OLED之光發射 光4、色坐標及效率特性。 "亥圖八之發射光譜係完全支持上述說明，而且在此種 It况下所發出之白光係具有一色坐標位置為（〇· 31， 〇·40)及一發光效率為 7.1cd/A，2.31m/W。 [第一比較實施例] 為了比較第一實施例至第三實施例，製備了一無激子 阻擔^構之qLed。而其特性則將在下文中加以說明。 厚度為1，800A之ITO (氧化銦錫）係被沉積在一玻 璃基板上，使形成_陽極。在該ITQ之上，藉由真空沉積 m MTDTA’使形成—厚度為4_之電洞注入層。在該電洞 注入層上，藉由真空沉積NPB，使形成一厚度為1〇〇A之 電洞傳輸層。 在該電洞傳輸層上，藉真空沉積NPB和紅熒烯，以製 備居度為140A之綠光發射層。在此步驟中，兩種材料係 同時沉積，而且該綠光發射層係含有97wt·%的之NPB與 3· Owt· %之紅熒烯。 緊接著，在該藍光發射層上，形成控制激子分布且具 有厚度為17A之白光平衡層。同時藉真空沉積Α1φ和香豆 21 1249368 素，以製備一具有厚度為l2〇A之紅光發射層。此處，該 紅光發射層中係具有99wt. %的Alq3和1· Owt· %的香豆素。 接下來，藉由真空沉積DPVBi，在該紅光發射層上形 成一厚度為180A之藍光發射層。 接著’在藍光發射層上形成一厚度為150A之電子傳 輸層。並藉由真空沉積一厚度為1〇A之LiF電子注入層及 一厚度為2, 000A之A1電極，使形成一 〇LED。The hole injection layer 2 and the hole transport layer 3 are formed in the hole. The above material has the hole injection layer 2 formed on the anode 1 and has a thickness of preferably between 400 A and 1,500 A; the hole transport layer 3 has a thickness of 100 A to 500 A. The difference between them is better. In the present embodiment, the OLED system includes an insulating substrate 1A which is generally used as a typical OLED. In essence, the substrate is preferably a glass substrate or a transparent plastic substrate having good transparency, a very flat surface, easy handling, and good water resistance. The anode 1 is composed of a material having excellent transparency and conductivity, such as indium tin oxide (ITO), Sn 2 , ZnO, etc., so as to have a thickness of between 1,0 qqa and 2,000 Å. 1249368 The cathode 9 is composed of a metal such as Li, Mg, A1, M-Li Ca Mg-In, Mg-Ag, etc., so as to have a thickness between i _A to 2 and just A. Here, the cathode 9 is the most It consists of a layer of high activity, low work function and a thickness of 5,00A i 5,000A. This two-layer structure is suitable for the stability and efficiency of the device. The electron transport layer 8 is composed of an -electron transport layer material such as tris(8-quinoquine)aluminum (Alq3) so as to have an intermediate degree. The white light balance layer 6 is composed of [N,N,-bis(naphthalenyl)phenyl]-N,N-bis(phenyl)biphenyldiamine (NpB) (=a-NpD), Has a thickness between 10A and 30A. Figure 2B is a diagram showing the energy level structure of a white germanium LED in accordance with an embodiment of the present invention. The white light balance layer 6 having an electron blocking effect is interposed between the red light emitting layer 5 and the blue light emitting layer 7; and the green light emitting layer having a low LUM〇 (lowest empty molecular domain) level 4 is inserted between the hole transport layer 3 and the red light emitting layer 5 to form a quantum well, that is, the exciton confinement structure 17. In this configuration, the desired thickness of the white light balancing layer 6 is between ι and 30 A depending on the contribution of white light generation. By adjusting the thickness of the white light balancing layer 6, the number of electrons reaching the red light emitting layer 5 and the green light emitting layer 4 can be controlled, and the number of electrons accumulated at the interface of the white light balancing layer 6 due to the energy wall can be controlled. . In order to form the exciton confinement structure 17, the green light-emitting layer 4 is required to be inserted between the hole transport layer 3 and the red light-emitting layer 5 to form a good-form energy level structure. As described above, the white OLED according to an embodiment of the present invention has a winter structure sequentially deposited in the following order: an anode, a hole injection layer, a hole transport layer, a green light emitting layer, a red light emitting layer, a white light balancing layer, Blue light emitting layer, electron transport layer and cathode. Wherein the red light emitting layer can be replaced by a yellow light emitting layer. Depending on the energy level or the arrangement of the matrix material used, the position of the red or yellow light-emitting layer 5 and the white light-balancing layer 6 can be exchanged in the sequentially accumulated organic layer. For example, as shown in FIG. 4, the device can be formed in the following order: anode, hole injection layer, hole transport layer, green light emitting layer, white light balance layer, red light emitting layer, blue light emitting layer, electron transport layer and cathode. As shown in FIG. 5, in order to obtain a highly efficient white OLED, the apparatus may further include an emission enhancement layer 23 between the blue emission layer 7 and the electron transport layer 8 to increase the emission efficiency of the blue emission layer 7. The emission enhancement layer 23 has a multilayer structure such as a blue emission layer/η-type layer, a blue emission layer/p-type layer, and a blue emission layer/n-type layer/p type layer. In the white OLED of the embodiment of the invention, excitons generated during operation of the device are controlled according to each contribution of the red light emitting layer 5, the green light emitting layer 4, and the blue light emitting layer 7, Appropriately distributed, and the white light balancing layer 6 is used to generate white light. Therefore, the maximum emission efficiency of each color can be obtained without depending on the structure of the red, green and blue light layers, such as the concentration of the dopant and the thickness of the emission layers. 16 1249368 Referring to FIG. 1, through the hole blocking effect of the hole blocking layers 10 and 15, a conventional white OLED is formed by the hole transmitting layers 1 and 13 and the layers of the emitting layers 11 and 14 The light guided at its interface emits white light. However, in the present invention, the white light balance layer 6 controls the electron distribution by the electron blocking effect, so that excitons 'unused in the blue light-emitting layer 7 can be dedicated to the red light-emitting layer 5 And the green light emitting layer 4. In the case of using a hole blocking layer (HBL) material as shown in Fig. 1, in order to satisfy the launching mechanism in this order, certain structural limitations are unavoidable. For example, the blue light-emitting layer 1 must be deposited in the red light, and the shots U, 14 and 21 are closer to the anode 1. However, the white OLED according to the embodiment of the present invention does not have this limitation. Moreover, by the doping of the hole transport layer 5 having a considerable sound for the lifetime of the organic optical device, it is possible to use energy between the subject and the object: a solution such as when the hole transport layer 5 is exposed When it comes to the system, it will shorten the problem and cause degradation. People! "Sub-resistance structure 17 is used to solve the problem in the _ field before the problem, that is, when the (four) light-emitting layer 4 is deposited on the anode 1 green and illusion rr equalization three kinds of balanced light (red, sub-barrier (4) This is limited and can be obtained. Because the excitons of the second are issued, the resolution of the low-recording problem is solved by 17 1249368. This problem is not only a typical problem of using the HBL of the transmitting device; It is also a typical problem of obtaining white light white OLEDs by three layers of emissive layers. Moreover, with the above quantum well structure, since the excess excitons that are not used by blue light and red light emission only participate in green light emission, they are not blocked. It is beneficial to contribute to the anode 1 during light emission. The anode 1 is one reason for the shortened service life of the device. Several preferred embodiments of the invention will be described in detail below, which will relate to the thickness and material of each layer. The following embodiments are provided to facilitate the understanding of the present invention, and the present invention is not limited to the embodiments. The following embodiments will be described with reference numerals in FIG. 3. [First Embodiment] ITO ( oxygen Indium tin) is deposited on a glass substrate 100 to form an anode 1 having a thickness of 1800 A. On the substrate 100 of the ITO coating, m-MTDTA is deposited by vacuum deposition to form a thickness of 400 A. Hole injection layer 2. On the hole injection layer 2, NPB is vacuum deposited to form a hole transport layer 3 having a thickness of 100 A. On the hole transport layer 3, by vacuum deposition Αίφ and Coumarin 6 forms a green light-emitting layer 4 having a thickness of 180 Å. In this step, the two materials are simultaneously deposited, and the green light-emitting layer 4 contains 99 wt·% of Alq3 and 1 wt.%. Coumarin 6. Next, by vacuum deposition of NPB and DCM, a red light emitting layer 5 having a thickness of 120 A is formed. NPB and DCM are simultaneously deposited in the same manner as the green light emitting layer 4 18 1249368. The red light emitting layer 5 contains 96 wt. % of NPB and 4. Owt. % of DCM. On the red light emitting layer 5, a white light balance capable of controlling the exciton distribution is formed by NPB vacuum deposition. Layer 6, the white light balancing layer 6 has a thickness of 17 A. Next, by vacuum deposition of DPVBi, A blue light emitting layer 7 is formed on the white light balancing layer 6, and an electron transporting layer 8 is formed on the blue light emitting layer 7 by vacuum deposition of Alq3. The blue light emitting layer 7 has a thickness of 180A, and the electron transporting layer 8 has a thickness of 120 A. Next, a LiF electron injection layer having a thickness of 10 A is deposited on the electron transport layer 8. Then, an A1 layer having a thickness of 2,000 A is deposited on the LiF layer to form a cathode. 9. In the obtained OLED, the electron blocking effect is expected to occur by the white light balancing layer 6 formed between the red light emitting layer 5 and the blue light emitting layer 7. Due to this effect, a part of the electrons contribute to the light emission of the blue light-emitting layer 7 doped with DPVBi, and another part of the electrons contributes the emission of orange-red light to the red light-emitting layer 5 doped with DCM, while other parts of the electrons are doped with incense The green light emitting layer 4 of the soybean contributes to the emission of green light. Figure 6 shows the light emission spectrum, color coordinates, and efficiency characteristics of a white OLED according to a first embodiment of the present invention. In the emission spectrum of Figure 6, it is easy to see that the red, green, and blue light lines uniformly contribute to the generation of white light, and their peaks are located near 455 nm, 510 nm, and 590 nm, respectively. At this time, the emitted white light has a color coordinate position of (0·33, 0·38), and the luminous efficiency is 6. lcd/A, 19 1249368 2.31 m/W 〇 [Second embodiment] The second embodiment The second embodiment has the following two characteristics which are different from the first embodiment as compared with the first embodiment. The red light-emitting layer 5 was formed by simultaneous deposition of NPB and rubrene under vacuum, and the red light-emitting layer 5 contained 97 wt.% of NPB and 3 wt.% of red phosphore. The white light balancing layer 6 has a thickness of 19 A to coordinate the purity of the color. As a result, in the second embodiment, a part of the excitons contributes yellow-orange light emission to the rubrene of the red light-emitting layer 5, and another part of the excitons contributes to blue light and green light emission, by controlling the white light The thickness of the balancing layer 6 changes to match the purity of the color. Figure 7 shows the light emission spectrum, color coordinates, and efficiency characteristics of a white light OLED according to a second embodiment of the present invention. Referring to the emission spectrum of Figure 7, all three colors of red, green, and blue contribute to white light emission, and each color has a maximum wavelength peak of 455 nm, 511 nm, and 560 nm, respectively. In this case, the white light emitted has a color coordinate position of (0.28, 0.36), and the luminous efficiency is 6.8 cd/A, 2.51 m/W. [Third Embodiment] The third embodiment is the same as the second embodiment, but in the third embodiment, the white light balance layer 6 is formed to have a thickness of 17A. As described above, the white light balance layer 6 controls the distribution of electrons that affect light emission. That is, the white light balance layer 6 controls the distribution of the excitons. For example, if the thickness of the 20 1249368 - W 9 6 formed between the red light emitting layer 5 and the blue light emitting layer 7 is reduced, the contribution of the light emitting layer 7 to white light emission is reduced due to the reduction of the electron blocking effect. It is reduced, and the contribution of the green light-emitting layer 4 and the red light-emitting layer 5 to white light emission is increased. Since the surface light is increased by the light, the color coordinate position of the white light is shifted to the long wavelength position. Figure 8 shows light emission light 4, color coordinates and efficiency characteristics of a white light OLED according to a third embodiment of the present invention. "Haitu Ba's emission spectrum fully supports the above description, and the white light emitted in this It state has a color coordinate position of (〇·31, 〇·40) and a luminous efficiency of 7.1 cd/A. 2.31m/W. [First Comparative Example] In order to compare the first to third embodiments, an excimer-free qLed was prepared. Its characteristics will be explained below. An ITO (Indium Tin Oxide) having a thickness of 1,800 A was deposited on a glass substrate to form an anode. On top of the ITQ, a hole having a thickness of 4 mm is formed by vacuum deposition of m MTDTA'. On the hole injection layer, a hole transport layer having a thickness of 1 Å was formed by vacuum deposition of NPB. On the hole transport layer, NPB and rubrene were vacuum deposited to prepare a green light emitting layer having a residence temperature of 140A. In this step, the two materials are simultaneously deposited, and the green light emitting layer contains 97 wt% of NPB and 3.0 wt% of rubrene. Next, on the blue light-emitting layer, a white light balance layer having a thickness of 17 A was formed which controlled the exciton distribution. At the same time, a red light emitting layer having a thickness of 12 Å was prepared by vacuum deposition of Α1φ and fragrant bean 21 1249368. Here, the red light emitting layer has 99 wt.% of Alq3 and 1.0% by weight of coumarin. Next, a blue light-emitting layer having a thickness of 180 A was formed on the red light-emitting layer by vacuum deposition of DPVBi. Next, an electron transport layer having a thickness of 150 A was formed on the blue light-emitting layer. A 〇LED was formed by vacuum deposition of a LiF electron injection layer having a thickness of 1 Å and an A1 electrode having a thickness of 2,000 Å.
圖九顯示依據本發明第一比較實施例白色0LED之为 ^射光δ晋、色坐標及效率特性。 參照圖九之光譜，我們可以發現，在該第一比較實教 例中’+沒有該激子阻擋效應，要想獲得自光係不可能的 因為藍光區之波峰顯著減小，這樣，僅有黃綠光區的波 對光發射做出貢獻。因此，所發之光乃具有—色 為㈣，。.⑷，而且係為一種淺黃色光。 置 [第一比較實施例]Figure 9 shows the white OLED of the white OLED according to the first comparative embodiment of the present invention. Referring to the spectrum of Fig. 9, we can find that in the first comparative example, '+ does not have the exciton blocking effect, and it is impossible to obtain the self-lighting system because the peak of the blue region is significantly reduced, so that only Waves in the yellow-green zone contribute to light emission. Therefore, the light emitted has a color of (4). (4), and is a kind of pale yellow light. [First Comparative Embodiment]
乐二杈佳實施例者比較，乃生產了 — …、白光平衡層之_，下文將對其特性進行說明。 -玻為1,8_之ΙΤ〇 (氧化銦錫)係被沉積 :璃基板上’以形成一陽極。在該ιτ〇上，藉由直空 積m，DTA，以形成—厚度為规之電洞注入 =電洞注入層上’藉由真空沉積猶，以形成—厚; 在該電洞注八層上，係沉心 層具有的_與3.〇wt.%之紅㈣，而該紅= 22 1249368 層則係藉由真空沉積DPVBi加以製備，使具有厚度200A。 接下來’沉積一厚度為160A之電子傳輸層，緊接著， 在該電子傳輸層上，藉UF真空沉積，以形成一厚度為 10A之LiF電子注入層。在該電子注入層上，藉Ai真空 沉積，以形成厚度為20(^之A1電極。 圖十顯示依據本發明第二比較實施例白色OLED之光 發射光譜、色坐標及效率特性。 參照圖十’全部激子都分布在該紅熒烯之綠光發射層 上’使發出黃光。也就是說，因為沒有依照該電子阻擋效 應進行讜藍光發射之白光平衡層，就沒有藍光發射。因 此，所發之光係具有色坐標位置為（〇46，〇47)。 同時’依據本發明之第一、第二和第三實施例及第一 和第二比較實施例所擁有亮度效率、最大亮度、量子效率 及色坐標之特徵則係均列於表1之中。 <表1> 亮度效率 (cd/A) 最大亮度 (cd/rri) 能量效率 (lm/W) 色坐標 (x，y) 第1實施例 6.1 _ 10,180 2.3 0.33, 0.38 第2實施例 6.8 ---- 11,570 2.5 0.28, 0.36 第3實施例 7.1 12,650 2.3 0.31, 0.40 第1比較實施例 8.1 ----- 13,500 3.5 0.37, 0.54 第2比較實施例 9.3 ~ 14, 620 3.8 0.46, 0.47 參照表1可以看出，從三色發射對白光發射的貢獻來 看，具備該激子阻擋效應與該白光平衡層之第一至第三實 施例中之GLED係較或沒有該激子阻擋效應結構或沒有該 23 1249368 白光平衡層之第一和第二比較實施例更適宜。 本發明之OLED係包括該能夠控制激子分佈之白光平 衡層，並且還包括能夠產生含有均衡數量紅光、綠光與藍 光之白光的激子阻擋結構。結果，依據本發明，所發出光 之顏色純度乃易於調節，而且利用多層發射層之最大發光 效率係大大地提高了該裝置之發光效率。因為產生了包含 全部三種顏色之白光，所以藉著使用彩色濾光片乃可生產 出一彩色顯示器。這些特性將本發明同傳統OLED區別開 來。傳統OLED在製作時考慮顏色之純度較考慮多層發光 層之最大發光效率要多，或產生僅含兩種顏色之白光。 不應認為本發明僅僅侷限於上文所述之特定範例，應該理解 為本發明涵蓋所附之申請專利範圍所述之全部範圍。不同之改 動，相當之製程，以及本發明適用之眾多結構，對那些熟習本技 術之人來說係顯而易見的，對其來說，本發明係經由觀看瞬時說 明書所導致而成者。 【圖式簡單說明】 參照附圖，經由各最佳實施例之詳細說明，本發明之 目的與其它優點將更為一目了然。其中： 圖一係說明了一僅有藍光與紅光發射層之傳統白色 OLED之能階結構圖。 圖二係說明了一具有三層發射層之傳統白色OLED之 能階結構圖。 圖三A係顯示依據本發明一實施例白色OLED之一種 層結構剖面圖。 24 1249368 圖三B係顯示依據本發明一實施例白色OLED之能階 結構圖。 圖四係顯示依據本發明另一實施例白色0LED之能階 結構圖。 圖五係顯示依據本發明再一實施例白色0LED之能階 結構圖。 圖六至圖八係顯示依據本發明幾個實施例白色0LED 之光發射光譜。 圖九和圖十係顯示兩比較實施例白色0LED之光發射 光譜、色座標及效率特性 【主要元件符號說明】 0 1 陽極 2 電洞注入層 3 電洞傳輸層 4 綠光發射層 5 紅光發射層 6 白光平衡層 7 藍光發射層 8 電子傳輸層 9 陰極 10 電洞傳輸與藍光發射層 11 電洞阻擋與紅光發射層 12 電子傳輸層 13 電洞傳輸與藍光發射層 14 紅光發射層 15 電洞阻擋層 16 電子傳輸層 17 激子限制結構 18 電洞傳輸層 19 藍光發射層 20 綠光發射層 21 紅光發射層 22 電子傳輸層 23 發射增強層 100 絕緣基板 25In comparison with the Le 杈 杈 实施 实施 实施 , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , - Glass is 1,8_ (Indium Tin Oxide) is deposited on the glass substrate to form an anode. On the ιτ〇, by the direct space product m, DTA, to form a thickness-based hole injection = hole injection layer 'by vacuum deposition to form a thick; in the hole eight layers Above, the sinking layer has _ and 3. 〇wt.% of red (four), and the red = 22 1249368 layer is prepared by vacuum deposition of DPVBi to have a thickness of 200A. Next, an electron transport layer having a thickness of 160 Å was deposited, and then, on the electron transport layer, vacuum deposition was performed by UF to form a LiF electron injection layer having a thickness of 10 Å. On the electron injecting layer, Ai was vacuum deposited to form an A1 electrode having a thickness of 20 Å. FIG. 10 shows light emission spectra, color coordinates, and efficiency characteristics of a white OLED according to a second comparative example of the present invention. 'All excitons are distributed on the green light emitting layer of the rubrene' to cause yellow light. That is, since there is no white light balance layer that emits blue light according to the electron blocking effect, there is no blue light emission. Therefore, The emitted light system has a color coordinate position of (〇46, 〇47). At the same time, the first, second and third embodiments and the first and second comparative embodiments according to the present invention have brightness efficiency and maximum brightness. The characteristics of quantum efficiency and color coordinates are listed in Table 1. <Table 1> Brightness efficiency (cd/A) Maximum brightness (cd/rri) Energy efficiency (lm/W) Color coordinates (x, y First Embodiment 6.1 _ 10,180 2.3 0.33, 0.38 Second Embodiment 6.8 ---- 11,570 2.5 0.28, 0.36 Third Embodiment 7.1 12,650 2.3 0.31, 0.40 First Comparative Example 8.1 ----- 13,500 3.5 0.37 , 0.54 Second Comparative Example 9.3 ~ 14, 620 3.8 0.46, 0.47 Referring to Table 1, it can be seen that, from the contribution of the three-color emission to the white light emission, the exciton blocking effect is provided with or without the exciton blocking effect of the GLED systems in the first to third embodiments of the white light balancing layer. The structure may be more suitable for the first and second comparative embodiments without the 23 1249368 white light balancing layer. The OLED system of the present invention includes the white light balancing layer capable of controlling the exciton distribution, and further comprising capable of generating a balanced amount of red light, green The exciton blocking structure of white light of light and blue light. As a result, according to the present invention, the color purity of the emitted light is easily adjusted, and the maximum luminous efficiency of the multilayer emission layer greatly improves the luminous efficiency of the device. It contains all three colors of white light, so a color display can be produced by using a color filter. These characteristics distinguish the present invention from the conventional OLED. The conventional OLED is considered to have a color purity in consideration of the multilayer light-emitting layer. The maximum luminous efficiency is greater, or white light containing only two colors is produced. The invention should not be considered limited to the above. The scope of the invention is to be construed as being limited by the scope of the appended claims. The present invention has been described with reference to the accompanying drawings. The invention and other advantages thereof will be more apparent from the detailed description of the preferred embodiments. Among them: Figure 1 illustrates the energy level structure of a conventional white OLED with only blue and red light emitting layers. Figure 2 is a diagram showing the energy level structure of a conventional white OLED having three emissive layers. Figure 3A is a cross-sectional view showing a layer structure of a white OLED according to an embodiment of the present invention. 24 1249368 FIG. 3B is a diagram showing the energy level structure of a white OLED according to an embodiment of the present invention. Figure 4 is a diagram showing the energy level structure of a white OLED according to another embodiment of the present invention. Figure 5 is a diagram showing the energy level structure of a white OLED according to still another embodiment of the present invention. Figures 6 through 8 show light emission spectra of white OLEDs in accordance with several embodiments of the present invention. Figure 9 and Figure 10 show the light emission spectrum, color coordinates and efficiency characteristics of the white OLEDs of the two comparative examples. [Main component symbol description] 0 1 Anode 2 Hole injection layer 3 Hole transmission layer 4 Green emission layer 5 Red light Emissive layer 6 White light balance layer 7 Blue light emitting layer 8 Electron transport layer 9 Cathode 10 Hole transport and blue light emitting layer 11 Hole blocking and red light emitting layer 12 Electron transport layer 13 Hole transport and blue light emitting layer 14 Red light emitting layer 15 hole barrier layer 16 electron transport layer 17 exciton confinement structure 18 hole transport layer 19 blue light emitting layer 20 green light emitting layer 21 red light emitting layer 22 electron transport layer 23 emission enhancement layer 100 insulating substrate 25