OLED外文文獻(xiàn)翻譯

1、文檔來(lái)源為 :從網(wǎng)絡(luò)收集整理.word 版本可編輯.歡迎下載支持ITO表面經(jīng)過(guò)常壓等離子體處理的有機(jī)發(fā)光器件的特性Chang Hyun JEONG, June Hee LEE, Yong Hyuk LEE, Nam Gil CHO, Jong Tae LIM,Cheol Hee MOON and Geun Young YOMEDepartment of Materials Science & Engineering, Sungkyunkwan University, Suwon, 440-746, KoreaPDP Division, Samsung SDI Co., Ltd., Ch

2、eonan, 330-300, Korea(Received October 4, 2004; accepted October 28, 2004; published December 10, 2004)摘要：本課題研究了 ITO表面經(jīng)過(guò)He/Q和He/SF6的常壓等離子混合氣體處理后的影響和有機(jī)發(fā)光器件的電學(xué)特性。經(jīng)過(guò)He/Q或He/SF6的等離子體處理后，由ITO/2-TNATA/NPD/Alq3/LiF/Al組成的OLED器件顯示出了很好的電學(xué)特性，例如：較低的導(dǎo)通電壓，高的功率效率等等。經(jīng)過(guò)He/SF6 處理的器件與He/O2處理過(guò)的相比有更卓越的電學(xué)性能。在用He/O2和He/SN

3、等離子體處理后，改善后的電性能與碳元素的減少和ITO表面Sn4+的聚集以及ITO中氟元素的摻雜濃度有關(guān)，這表明表面處理后工作性能 有所提高。關(guān)鍵詞：ITO,表面處理，常壓等離子體，OLED He/Q, He/SF6OLE況示器件之所以能得到廣泛的研究是因?yàn)樗麄兙哂蟹浅?yōu)越的特性，例如：快速的響應(yīng)時(shí)間，較低的工作電壓，較高的量子效率等等。此外，與其他的平板顯示器相比，例如：液晶顯示器和等離子顯示器，OLEDB示器有更簡(jiǎn)單的工藝流程和更低的制造成本。目前，對(duì)于基板尺寸小于370mm*470mm的器件，通常在一個(gè)真空腔體內(nèi)利用多層蒸發(fā)技術(shù)來(lái)完成，而用于制造接近920mm*730mmJ大尺寸的沉積技術(shù)

4、目前正處于研發(fā)當(dāng)中。此外，利用噴墨打印技術(shù)代替真空蒸發(fā)技術(shù)來(lái)制作高分子有機(jī)OLED器件正處于積極的研發(fā)階段。對(duì)于OLE端件，需要一種透光性高的透明導(dǎo)體，在各種透明導(dǎo)體中，具有高傳導(dǎo)性和高透光性的ITO被廣泛的應(yīng)用。為形成 OLE端件，有機(jī)材料被沉積在ITO上，形成一個(gè)低阻值的歐姆接觸，OLED器件在 ITO 和有機(jī)材料之間形成的接觸電阻可以通過(guò) ITO 表面預(yù)處理來(lái)改變。 ITO 是一個(gè)非化學(xué)計(jì)量 化合物，化學(xué)成分可以很容易的改變。因此，為了改善OLE端件中ITO和有機(jī)材料間的接觸特性，在ITO表面沉積有機(jī)材料之前進(jìn)行處理是非常重要的。作為表面處理方法的低壓等離子技術(shù)、UV/O技術(shù)、和濕處理均

5、被用于去除有機(jī)雜質(zhì)和改善ITO表面特性。然而，這些技術(shù)價(jià)格非常昂貴，而且低壓等離子技術(shù)和UV/O3 技術(shù)難以用于規(guī)模較大的基板，并且，濕處理法還存在環(huán)境問(wèn)題。為了代替低壓等離子體技術(shù)和濕處理等技術(shù)，以常壓等離子體，如電暈放電、電介質(zhì)阻擋放電、大氣等離子流體等為處理技術(shù)來(lái)處理電子材料、電極材料、生物材料和結(jié)構(gòu)材料的方法正在積極地開(kāi)發(fā)當(dāng)中。本課題研究了利用常壓等離子體來(lái)處理和清潔 OLEDITO玻璃表面的價(jià)值。作為常壓等離 子清潔技術(shù)，即一個(gè)修改了的 DB/術(shù)，能被用于大規(guī)模的環(huán)境中并且展現(xiàn)了一個(gè)比傳統(tǒng)DBEM高密度的等離子體。通過(guò)改變?cè)谛薷牡?DBD昆合氣體，這些混合氣體在ITO的表面特性和形成

6、干凈的ITO 玻璃的OLE端件電學(xué)特性方面的影響正在觀察中。圖1為處理ITO玻璃表面的常壓等離子體設(shè)備圖。如圖所示，修改過(guò)的DBD勺研究設(shè)備由代替一個(gè)平板電極作為功率電極的錐體形狀的多針電極，作為接地端的另一塊平板電極以及兩電極間的電介質(zhì)材料組成。使用多針電極代替平板電極，通過(guò)在針的尖端形成一個(gè)類(lèi)似于具有較高穩(wěn)定性的電暈放1文檔來(lái)源為：從網(wǎng)絡(luò)收集整理.word版本可編輯.歡迎下載支持電和輝光放電的高電場(chǎng)，從而能夠獲得一個(gè)高的離子體密度和低壓交流下的氣體擊穿。多針功率電極連接到頻率為2030千赫茲、電壓 為315千伏的交流電壓，平板接地 電極接地。He(10 slm)/O2(3 slm)和 He

7、(10 slm)/SF 6(100 sccm)的混合 氣體被應(yīng)用于OLEDITO表面的 清洗。在等離子處理前，所有的ITO 玻璃均用有機(jī)溶劑清洗過(guò)。這些氣 體的最佳成分通過(guò)接觸角和ITO基 板碳含量來(lái)選擇，接觸角利用專(zhuān)用 工具來(lái)測(cè)量，碳含量通過(guò)改變由 03 slm 的氧流速、0500 sccm 的 SF6流速以及10slm的氨流速的X 射線光電譜線來(lái)測(cè)量。交流電源為 25千赫茲、10千伏，持續(xù)工作30'wwvwww'Mulli-plii powerdtdrodtrro3立G1向Fip 1. Schciikitic di與ram of the aimosplicnL preure

8、 pLnia cquipincm usM for the surface treamiiMH ct 11U glass.4秒。經(jīng)過(guò)He/Q和He/SF6等離子混合氣體清潔后的ITO表面組成用X射線源為1486.6 eV的X射線光 電子能譜來(lái)研究。在沒(méi)有破壞真空的條件下，通過(guò)在潔凈的ITO上OLE附料的熱分解和電極材料的順序蒸鍍制備成了 OLED件。研究的這個(gè) OLE郵件的Z勾為 ITO/2-TNATA(60 nm)/NPD(20 nm)/Alq 3(40 nm)/LiF(1nm)/Al(100 nm)。有機(jī)材料、氟化鋰和鋁的沉積速率分別為0.3 -0.5 A/s、0.1 A/s、0.5 -5

9、A/s ,器件的有效面積為 4mmi OLED器件的電學(xué)特性由電子儀器測(cè)量得到，光學(xué)特性通過(guò)使用皮安計(jì)測(cè)量 OLE湍件光發(fā)射引起的光電流來(lái)得到。圖2所示為ITO經(jīng)過(guò)He(10 slm)/O 2(3 slm) 和He(10 slm)/SF 6(100 sccm)常壓等離子混合氣體 處理的OLE端件的特性，例如：(a)亮度與電壓的關(guān)系、(b)亮度與電流密度的關(guān)系、(c)功率效率 與電流密度的關(guān)系。作為參考，圖中還包括了沒(méi)經(jīng)過(guò)等離子處理的OLED器件的特性。如圖2 (a)所示,經(jīng)過(guò)等離子體 He(10 slm)/O 2(3 slm)和He(10 slm)/SF 6(100 sccm)處理后的器件的開(kāi)

10、啟電壓(定 義為發(fā)出1 cd/m2的亮度所需的電壓)分別為 3.6V和3.2V,然而未經(jīng)等離子體處理的器件的開(kāi)啟電壓 為4.2V。因此，經(jīng)過(guò)等離子體處理后開(kāi)啟電壓減小了，而且經(jīng) He(10 slm)/O 2(3 slm)處理后的器件的 開(kāi)啟電壓比經(jīng)He(10 slm)/SF 6(100 sccm)處理后的電壓低。此外，如圖 2 (b)所示，在同一發(fā)光強(qiáng)度 的條件下，經(jīng) He(10 slm)/SF 6(100 sccm)處理的OLEDl!現(xiàn)出了最低的電流密度，而沒(méi)經(jīng)處理的 OLED 器件表現(xiàn)出了最高的電流密度。通過(guò)對(duì)電流密度的測(cè)量，得到了用三種方法He(10 slm)/SF 6(100 sccm

11、)、 He(10 slm)/O 2(3 slm)和未做處理的三個(gè)器件的最高功率效率分別為0.93 Lm/W、0.75 Lm/W 和0.58Lm/W)因此，經(jīng)過(guò) He(10 slm)/SF 6(100 sccm)處理的OLE湍件顯示了最佳的電學(xué)性能。(UJFPU)Q>uuau5小二 Go-Hr>.xiaib-j oC g IC 1214Voltage (V)Kiftonr7000經(jīng)過(guò) He(10 slm)/SF 6(100 sccm)處理的 OLEDibV0 M 1D0150500550Current density (inA/cm1)-kWQ simj 匕6 口出嗣1翼融4：則 I

12、npul wMaye： 10 kV Processing lima： Jd器件的電特性的改善看上去與去除ITO表面的有機(jī)雜質(zhì)和經(jīng)處理的ITO工作性能的改變有關(guān)。表1顯示了通過(guò)XPS測(cè)量的未經(jīng)處理、He(10 slm)/O 乂3 slm)和He(10 slm)/SF 6(100 sccm)三種處理方法后 的ITO表面的組成。表中顯示，經(jīng)等離子處理后，ITO表面碳元素的含量顯著的減少，而且，經(jīng)He(10slm)/SF 6(100 sccm)處理后 的ITO表面碳含量最少，因 此，有機(jī)清洗后殘留的有機(jī) 雜質(zhì)被等離子體清除了很 多，有機(jī)雜質(zhì)的去除被認(rèn)為 改善了 OLED勺性能。f.4.2C.8.E.4

13、2.O IL 1 1 o OO.G 。(芝 E)Auuo石一toJoModnet&renoeInput voltage: lOkVProcessing time： 3Qsec05010015020C250Current density (mA/cmz)Fig. 2. Characteristics of the OLEDs fabricated on the ITO glass cleaned by the atmospheric pressure plmi udngsJm) andHeOsIml/SFti 1()0sccm) gas mixtures (a) Iujninescenc

14、c- voltape, <b) lumirx:sccncc-current dcnsitj and (c) power cffidcncy-currcnt density. .Xs a reference, the ckiracic ri sties of the OLED <lcice hbricaiccl 5 ithout plasma cleaning arc included.當(dāng)比較用 He(10 slm)/O 2(3 slm)和 He(10 slm)/SF 6(100 sccm)處理的 ITO表面組成時(shí)發(fā)現(xiàn)，在用 He(10 slm)/SF 6(100 sccm) 清潔的

15、ITO表面的氧被12% 的氟代替，然而卻沒(méi)有發(fā)現(xiàn) 硫元素。ITO中氟的摻雜提 高了 ITO的電學(xué)特性，從而 推理出氧化錫中摻雜氟可以 提高空穴的注入效率。此外, X射線電子譜線數(shù)據(jù)顯示， 即使在等離子處理后，錫錮 比值沒(méi)有顯著變化，而表面 Sn4+的含量卻明顯減少。 Sn3c5/2在峰值處可以分解成Sn2+和Sn4+的氧化物。圖3顯示了將Sn3cl5/2的峰值分解成Sn2+和Sr4+的XPS窄掃描數(shù)據(jù)。如圖所示，經(jīng) 過(guò)等離子體處理后的 Sn4+的最高值有所減小，在經(jīng) He(10 slm)/SF 6(100 sccm)處理后為最低的峰值。據(jù)報(bào)道，通過(guò)用In 3+代替Sn4+的位置來(lái)減少Sn4+的

16、含量，Sn4+的減少使n型的費(fèi)米能級(jí)向中間能帶改變， 從而提高了 ITO的工作性能。因此，經(jīng)用 He(10 slm)/SF 6(100 sccm)處理的OLED器件的改善也與增 加氟元素和減少I(mǎi)TO表面Sn4+的含量來(lái)除去碳雜質(zhì)以提高工作性能有關(guān)。I able I. Composition of the ITO surfaces not created (as is) and trcattxiwith He( 10siniJ/O?(3slm) and Hc 10slrn)/SFg(lOOsocm) measured by XPS.Atomic conccntratnsn (%) Ttcatme

17、ni method Cis I 口 3%2Sn3dM01s FIs Sn/lnAs isHc/Oi plasma(10slm/3 slin)He/SFb plasma(10 slm/1 (Mlseem)12.831.9G 7 Q7 7J 右J.8.6322A.450.9A0 1370.1301220,127結(jié)論，利用常壓等離子體設(shè)備使He(10 slm)/O 2(3 slm)和He(10 slm)/SF 6(100 sccm)的混合氣體來(lái)處理ITO玻璃的表面以及它對(duì)ITO表面特性和ITO經(jīng)過(guò)處理的OLE湍件的特性的影響已經(jīng)得到了研究。經(jīng)過(guò)He (10 slm)/SF 6

18、(100 sccm)處理的OLE湍件擁有最好的電學(xué)特性，例如：最低的開(kāi)啟電壓(在鳧度均為 1cd/m2的前提下， He/SB處理后為3.2V, He/6處理后為3.6V,未處理的為4.2V)、最高的亮度(在相同的電流密度 下)和最高的功率效(=E- a=5uqc-率(He/SF6處理后為100000.93Lm/W( He/Q處理 后為0.75Lm/W(未處 理的為 0.58Lm/W)。He(10 slm)/SF 6(100 sccm)等離子體處理 的OLED器件性能的 改善與ITO表面有機(jī) 雜質(zhì)的去除、Sn4+的30000non486A0&Binding energy (eV)4906

19、000050000Fig一 工 Nartxiw xcan XPS or (hr deconvidurul Sir4- tind Sni4+ pen心 from the SiiRds,： peak* of the F I O surfiivc Irciilcd with FIc(10,ilm)/ O二門(mén)3m) diuJ Tfc(10%1in)/SF6i lOOsccin). The XPS ddlH of the ITO in face nut IrcatcJ by ihc plaMiiH i al so iiK lixicd.ITO的影響含量的降低以及ITO表面氟元素的摻雜有關(guān)，而且表明了 I

20、TO性能的提高。因?yàn)槌旱入x子體不需要 真空室，所以能夠很容易安裝負(fù)載室并應(yīng)用于尺寸大于 730mm*920mm基板，常壓等離子體可以成功 的應(yīng)用于商業(yè)制造OLE邛ITO的清洗環(huán)節(jié)。SF6低壓等離子體處理和常壓等離子體處理對(duì)文檔來(lái)源為 :從網(wǎng)絡(luò)收集整理.word 版本可編輯.歡迎下載支持正在進(jìn)一步觀察中。這個(gè)課題得到了商務(wù)部、 工業(yè)和能源部以及韓國(guó)科技部的國(guó)家研究實(shí)驗(yàn)室計(jì)劃 (海軍研究實(shí)驗(yàn)所)的支持。參考文獻(xiàn)1) C. W. Tang and S. A. VanSlyke: Appl. Phys. Lett. 51 (1987) 913.2) F. Li, H. Tang, J. Andere

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26、 P. Agnihotri, A. K. Sharma, B. K. Gupta and R. Tangaraj: J. Phys.D. 11 (1978) 643.19) A. Andersson, N. Johansson, P. Broms, N. Yu, D. Lupo and R.Salaneck: Adv. Mater. 10 (1998) 859.Characteristics of Organic Light-Emitting Devices by the SurfaceTreatment of Indium Tin Oxide Surfaces Using Atmospher

27、ic PressurePlasmasChang Hyun JEONG, June Hee LEE, Yong Hyuk LEE, Nam Gil CHO, Jong Tae LIM,Cheol Hee MOON and Geun Young YOMEDepartment of Materials Science & Engineering, Sungkyunkwan University, Suwon, 440-746, KoreaPDP Division, Samsung SDI Co., Ltd., Cheonan, 330-300, Korea(Received October

28、4, 2004; accepted October 28, 2004; published December 10, 2004)5ABSTRACT ： This study examined the effects of a He/O 2 and He/SF6 atmospheric pressure plasma surface treatment of indium tin oxide(ITO) glass on the ITO surface and electrical characteristics of organic light emitting diodes (OLEDs).

29、The OLEDs composedof ITO glass/2-TNATA/NPD/Alq 3/LiF/Al showed better electrical characteristics, such as lower turn-on voltage, higher power efficiency, etc., after the He/O 2 or He/SF6 plasma treatment. The He/SF6 treatment resulted in superior electrical characteristics compared with the He/O2 tr

30、eatment. The electrical improvement as a result of the He/SF 6 and He/O2 plasma treatments is related to the decrease in the carbon and Sn4t concentration on the ITO surface and fluorine doping of the ITO possibly indicating a change in the work function as a result of the treatments. DOI: 10.1143/

31、KEYWORDS ： ITO, surface treatment, atmospheric pressure plasma, OLED, He/O2, He/SF6Organic light emitting diode (OLED) displays have been extensively studied due to their superior properties such as faster response time, lower operating voltage, higher quantum efficiency, etc. in addition to the sim

32、pler deposition processing and lower manufacturing cost compared with other flat panel displays such as liquid crystal displays and plasma display panels.1 為 Currently, these devices are manufactured in a high vacuum chamber for substrate areas smaller than 370mm 470mm using a multilayer evaporation

33、 technique for monomer organics, and deposition techniques for the large area substrates close to 920mm 730mm are currently under development. In addition, OLED displays utilizing polymer organics, which use inkjet printing instead of vacuum evaporation, are actively being studied4.,5)On OLED device

34、s, a transparent conductor is used for the higher optical transparency, and among the various transparent conductors, indium tin oxide (ITO) is the most widely used due to its high conductivity and transparency. In order to form OLED devices, the organic monomers are deposited on patterned ITO glass

35、 for the formation of a low resistive ohmic contact. The contact resistance between the ITO and organic materials of the OLED devices can be altered by the ITO surface preparation due to the organic materials on the ITO glass surface and the change in the ITO composition as a result of the ITO surfa

36、ce preparation method. ITO is a nonstoichiometric compound. Therefore, the chemical composition can be easily changed.6) Consequently, in order to improve the contact properties between the ITO and the organic material of the OLED, the surface treatment of the patterned ITO before depositing the org

37、anic materials is very important.6 13) As surface treatment methods, low pressure plasma techniques，0,12) UV/O 3 techniques”1) and wet treatments12,13) have been used to remove the organic materials and improve the ITO surface properties. However, these techniques are expensive and difficult to scal

38、e to large areas using low pressure plasma and UV/O3 techniques. In addition, there are environmental issues in the case of wet treatment.Atmospheric pressure plasma such as a corona discharge,14) dielectric barrier discharge (DBD), 15,16) atmospheric plasma jet,17) etc. for the treatment of various

39、 surfaces applied to electric materials, electronic materials, biomaterials, structural materials, etc. have been actively studied in order to replace low pressure plasma techniques, wet processing, etc. This study examined the potential of using atmospheric pressure plasma for the surface treatment

40、 and cleaning of ITO glass for OLED devices. As an atmospheric pressure plasma cleaning technique, a modified DBD, which can be scaled to large areas and show a higher plasma density than conventional DBD, was used. By varying the gas mixture in the modified DBD, the effects of the gas mixture on th

41、e characteristics of the ITO surface and on the electrical properties of the OLED devices formed on the cleaned ITO glass were investigated.Figure 1 shows a schematic diagram of the atmospheric pressure plasma equipment used in this study for 6文檔來(lái)源為：從網(wǎng)絡(luò)收集整理.word版本可編輯.歡迎下載支持the surface treatment of I

42、TO glass. As shown in the figure, the modified DBD used in this study was composed of a pyramid shaped multi-pin electrode as the power electrode instead of a plate electrode, a plate electrode as the ground electrode, and dielectric materials on both electrodes. Using the multi-pin electrode instea

43、d of a blank plate electrode, a higher plasma density and gas breakdown at a lower AC voltage could be obtained by forming a high electric field on the tip of the pins similar to the corona discharge with a higher stability and glow discharge shape instead of a filamentary discharge shape. The AC vo

44、ltage in the range from 3 to 15 kV with a frequency of 20 -30 kHz was connected to the multi-pin power electrode and the ground was connected to the plate ground electrode.Fig. 1. Schematic diagram of the atmospheric pressure plasma equipmentused for the surface treatment of ITO glass.He(10 slm)/O2(

45、3 slm) and He(10 slm)/SF6(100 sccm) were used as the ITO surface cleaning gas mixtures for the OLED devices. Before the plasma treatment, all the ITO glasses were cleaned with an organic solvent. These optimum gas compositions were selected after measuring the contact angle by a contact angle measur

46、ing tool and the carbon contents on the ITO surface by X-ray photoelectron spectroscopy (XPS, VG Microtech Inc., ESCA2000) after varying the O 2 flow rate from 0 to 3 slm and the SF6 flow rate from 0 to 500 sccm with a He flow rate of 10 slm. The AC voltage used was 10 kV at 25 kHz and the processin

47、g time was 30 seconds. The composition of the ITO surface after cleaning with the He/O2 and He/SF6 plasma was investigated by XPS using Al KX-ray source of 1486.6 eV.The OLED devices were fabricated on the cleaned ITO by the thermal evaporation of the OLED materials andelectrode materials sequential

48、ly without breaking the vacuum.The OLED structure used in this study was ITO glass/2-TNATA(60 nm)/NPD(20 nm)/Alq 3(40 nm)/LiF(1 nm)/Al(100 nm). The deposition rates of the organic materials, LiF, and Al were 0.3 -0.5? /s, 0.1 ? /s, and 0.5 -5 ? /s, respectively. The fabricated device active area was

49、 4mm2. The electrical characteristics of the fabricated OLED devices were measured using an electrometer (Keithley 2400) and the luminescence characteristics were determined by measuring the photocurrent induced by light emission from the OLEDs using a picoammeter (Keithley 485).Figure 2 shows the c

50、haracteristics of the OLEDs fabricated on the ITO glass cleaned by the atmospheric pressure plasma using the He(10 slm)/O2(3 slm) and He(10 slm)/SF6(100 sccm) gas mixtures such as (a) luminescencevoltage, (b) luminescence-current density, and (c) power efficiency-current density. As a reference, the

51、 characteristics of the OLED device fabricated without plasma cleaning were included. As shown in Fig. 2(a), the turn-on voltages of the devices (defined as the voltage required to deliver a luminescence of 1 cd/m2) after the He(10 slm)/O2(3 slm) and He(10 slm)/SF6(100 sccm) treatment were 3.6V(h)/O

52、OJHJOJLW.JQO3200JCurrent density (mA/cm )一rvgrvrig (10(lm/3-x- Hc/SR Him/100 jrecffi)hput vottage： 10 kVilm». 3 口 tKand 3.2 V, respectively, while the turn-on voltage of the device without the plasma treatment was 4.2 V. Therefore, after the plasma treatment, the turn-on voltage was decreased a

53、nd the He(10 slm)/O2(3 slm) treatment showed a lower turn-on voltage than the He(10 slm)/SF6(100 sccm) treatment. In addition, as shown in Fig. 2(b), the OLED treated by He(10 slm)/SF6(100 sccm) showed the lowest current density at the same emission intensity while the81003文檔來(lái)源為 :從網(wǎng)絡(luò)收集整理.word 版本可編輯.

54、歡迎下載支持OLED fabricated without the plasma treatment showed the highest current density. When the power efficiency was measured as a function of the current density, the highest power efficiencies were 0.93 Lm/W, 0.75 Lm/W, and 0.58 Lm/W for the He(10 slm)/SF6(100 sccm) treated sample, He(10 slm)/O2(3

55、 slm) treated sample, and the non-treated sample, respectively. Therefore, after the He(10 slm)/SF6-(100 sccm) treatment, the device showed the best electricalperformance.Fig. 2. Characteristics of the OLEDs fabricated on the ITO glass cleaned by the atmospheric pressure plasma using He(10 slm)/O2(3

56、 slm) and He(10 slm)/SF6(100 sccm) gas mixtures. (a) luminescence-voltage, (b)luminescence-current density, and (c) power efficiency-current density.As a reference, the characteristics of the OLED device fabricated withoutplasma cleaning are included.The improved electrical characteristics shown for

57、 the OLED after the He(10 slm)/SF6(100 sccm) treatment appeared to be related to the removal of the remaining contaminants on the ITO surface and the change in the work function of the ITO as a result of the plasma treatment. Table I shows the composition of the non-treated (as is) and He(10 slm)/O2

58、(3 slm) and He(10 slm)/SF6(100 sccm) treated ITO surface measured by XPS. As shown in the table, carbon contamination on the surface decreased significantly as a result of the plasma treatment and the ITO surface after the He(10 slm)/SF6(100 sccm) treatment showed the lowest carbon content on the surface. Therefore, the organic contaminants remaining after organic cleaning were removed further after the plasma cleaning, and the removal of the organic contaminants is believed to be partially responsi