本文選題：有機(jī)發(fā)光二極管 + 電子-空穴對��； 參考：《西南大學(xué)》2016年博士論文

【摘要】：有機(jī)電致發(fā)光(electroluminescence,EL)器件是以有機(jī)材料為活性層,在外加電場作用下輻射發(fā)光的有機(jī)半導(dǎo)體器件,又稱為有機(jī)發(fā)光二極管(organic light-emitting diode,OLED)。自從鄧青云(C.W.Tang)博士等1987年發(fā)明了三明治型有機(jī)雙層薄膜電致發(fā)光器件以來,有機(jī)電致發(fā)光材料與器件被廣泛研究并取得了很大進(jìn)展。運(yùn)用有機(jī)材料作為電子器件有很多優(yōu)勢,如它們制備簡單、化學(xué)可調(diào)控,可以制作柔性和透明的器件。因此,除了作OLED外,還可以用來制備有機(jī)太陽能電池(OSC),有機(jī)自旋閥(OSV),有機(jī)場效應(yīng)晶體管(OFET)。近二十多年來,這些有機(jī)半導(dǎo)體器件迅猛發(fā)展,取得了大量進(jìn)展,還催生了一門新型學(xué)科—有機(jī)電子學(xué)。它是一門既涉及化學(xué)(如有機(jī)化學(xué)、光化學(xué)和高分子化學(xué)等),又牽連物理學(xué)(界面物理、固體物理、半導(dǎo)體物理及有機(jī)材料與器件內(nèi)電子轉(zhuǎn)移、自旋輸運(yùn)和電子-空穴對(e-h對)的自旋混合等過程)。有機(jī)電子學(xué)中有機(jī)半導(dǎo)體器件的工作原理和內(nèi)部微觀機(jī)制的相關(guān)知識(shí),不但可以很好地幫助我們認(rèn)識(shí)有機(jī)半導(dǎo)體器件的性質(zhì),還為我們優(yōu)化有機(jī)電子器件指明方向。但是,以碳?xì)錇榛A(chǔ)的有機(jī)半導(dǎo)體材料與傳統(tǒng)的無機(jī)半導(dǎo)體材料相比,在電子結(jié)構(gòu)、電子輸運(yùn)、載流子遷移率等方面都明顯不同,我們不能完全按照無機(jī)半導(dǎo)體的方法來研究它們,對其內(nèi)部機(jī)制認(rèn)識(shí)得也并不完善。例如有機(jī)半導(dǎo)體器件中由正負(fù)極化子組成e-h對之間通過自旋混合相互影響和轉(zhuǎn)換,從而對器件性能產(chǎn)生重要影響。參與的自旋相關(guān)的混合過程認(rèn)識(shí)得并不全面,提出的觀點(diǎn)有分歧甚至相互沖突,這就需要我們對e-h對自旋混合過程進(jìn)行進(jìn)一步的研究。分析研究e-h對自旋混合過程的方法很多,常用的方法就是測量有機(jī)器件的吸收光譜與發(fā)射光譜、瞬態(tài)光譜、發(fā)光-電壓-電流(B-I-V)特征曲線等。并根據(jù)需要,通過改變器件結(jié)構(gòu)、測量溫度和偏置電壓甚至更換功能層的方法調(diào)控混合過程從而改變它們的光譜和特征曲線等來確定內(nèi)部機(jī)制的種類。但有些自旋混合過程很難用這些方法區(qū)分,如三重態(tài)激子湮滅(TTA)和反系間竄越(RISC)導(dǎo)致的延遲熒光的瞬態(tài)光譜特征相似,也無法用B-I-V曲線區(qū)分.幸運(yùn)的是,有機(jī)半導(dǎo)體器件在外加磁場作用下,其發(fā)光、電流甚至光譜都會(huì)發(fā)生相應(yīng)改變,且這種變化往往是磁場的函數(shù),我們稱之為有機(jī)磁場效應(yīng)(OMFE)。它主要包括磁致發(fā)光效應(yīng)(MEL)和磁致電導(dǎo)效應(yīng)(MC)。不同自旋混合過程往往具有不同的MEL和MC特征曲線,這些曲線可以作為e-h對自旋混合過程的身份標(biāo)簽或者指紋,為我們提供高效分析有機(jī)半導(dǎo)體器件內(nèi)部機(jī)制的非接觸手段。例如,因?yàn)樯厦嫣岬降腡TA和RISC的MEL指紋明顯不一樣,可以很容易通過磁效應(yīng)進(jìn)行區(qū)分。目前,人們已經(jīng)在OSC、OFET、OSV和OLED中都發(fā)現(xiàn)了磁效應(yīng),但前3種器件磁效應(yīng)主要是MC。在OLED中,空穴h和電子e在電場庫侖力作用下相遇形成e-h對,這些e-h對在不同分子上時(shí)為極化子對,在同一分子上是激子。自旋法則決定的單、三重態(tài)e-h對比例為1:3。熒光發(fā)光器件只有25%的單重態(tài)激子型e-h對才對發(fā)光有貢獻(xiàn),75%的三重態(tài)e-h對的退激輻射是自旋禁阻的。因此,三重態(tài)e-h對的壽命可以達(dá)到10~(-6)到10~2秒量級,比單重態(tài)e-h對的10~(-9)秒的量級大得多,這就使三重態(tài)e-h對有足夠長的時(shí)間與其它e-h對和載流子進(jìn)行自旋混合。這些自旋混合過程包括系間竄越(ISC)和單重態(tài)激子分裂(STT);還有兩個(gè)T激子通過湮滅過程產(chǎn)生1個(gè)S激子的過程(TTA),以及T與載流子(C)或極化子(P)間的相互作用(TCA或TPI)等。它們會(huì)改變單、三重態(tài)e-h對的比例,從而對器件的發(fā)光和電流都產(chǎn)生重要影響。而外磁場會(huì)通過抑制這些過程反過來改變器件的發(fā)光和電流,從而產(chǎn)生MEL和MC。我們可以同時(shí)通過MEL和MC的特點(diǎn)研究這些混合作用的特點(diǎn)以及它們對器件性能的影響。同時(shí),通過器件結(jié)構(gòu)、溫度、界面修飾和摻雜等技術(shù)調(diào)控這些自旋混合,我們還可以對MEL和MC等磁效應(yīng)的調(diào)控,實(shí)現(xiàn)特定功能的器件,如有機(jī)磁傳感。因此,通過OLED研究e-h對及其與極化子之間的自旋混合,將比其它有機(jī)半導(dǎo)體器件更有優(yōu)勢。本論文以O(shè)LED器件為研究對象,通過改變電子傳輸材料為活躍層的器件的電極及其蒸鍍方式來修飾有機(jī)-金屬界面、更換空穴傳輸材料為活躍層的器件的電極來調(diào)控電子注入和缺陷數(shù)目、往有機(jī)活躍層中引入Fe_3O_4雜質(zhì)或者結(jié)構(gòu)缺陷,對器件內(nèi)的自旋混合過程進(jìn)行調(diào)控。再結(jié)合不同溫度下的光譜、I-B-V曲線等手段,分析不同混合過程的磁效應(yīng)特征,完善自旋混合過程的指紋庫。最后,利用已知的自旋混合過程的指紋特征,對器件內(nèi)可能發(fā)生的自旋混合過程進(jìn)行分析量化,提出了通過改變分子間距調(diào)控單、三重態(tài)e-h對相互轉(zhuǎn)換來提高器件熒光效率的方法。具體內(nèi)容分為如下幾個(gè)章節(jié):第1章介紹了有機(jī)自旋電子學(xué)的基本概念與研究內(nèi)容相關(guān)的基本知識(shí)。特別是OLED中e-h對形成過程、種類以及與其它激子或者電荷等自旋混合過程的形式、相互作用類型與相關(guān)微觀模型與機(jī)制。如超精細(xì)相互作用模型(HFI)、自旋軌道耦合機(jī)制(SOC)、“Δg”機(jī)制、三重態(tài)激子湮滅(TTA模型)、單重態(tài)激子解離(STT)、雙極化子模型(Bipolaron)、三重態(tài)-電荷作用(TCA)等。第2章詳細(xì)介紹了本實(shí)驗(yàn)小組制備OLED的方法、流程及樣品的測試。重點(diǎn)介紹有機(jī)層和金屬電極的真空蒸鍍方法、以及光譜分析、磁效應(yīng)分析等測量分析方法和技術(shù)。第3章選用典型的電子傳輸兼發(fā)光材料Alq_3作為活躍層,制備了結(jié)構(gòu)為ITO/Cu Pc/NPB/Alq_3/金屬電極的OLED器件。在該器件中,我們分別采用Al,Cu,Au和Li F/Al電極來改變電極功函數(shù)和原子序數(shù)。并通過改變金屬電極的真空蒸鍍方法(分子束沉積、熱阻蒸發(fā)和電子束蒸發(fā))來修飾有機(jī)金屬界面,最終實(shí)現(xiàn)了對器件內(nèi)e-h對自旋混合過程的調(diào)控。然后通過測量這一系列器件在20 K~300 K溫度范圍內(nèi)的MEL和MC來分析調(diào)控結(jié)果。實(shí)驗(yàn)結(jié)果顯示,當(dāng)采用分子束沉積法去蒸鍍功函數(shù)高、原子序數(shù)大電極時(shí),器件的MEL在高場出現(xiàn)明顯下降,且這種下降無法用已有的引起高場下降的e-h對自旋混合模型,如TTA、TCA、雙極化子和Δg機(jī)制來解釋。我們提出了一種新的模型來解釋這種高場下降:有機(jī)金屬界面修飾可以改變e-h對復(fù)合區(qū)的位置,高功函數(shù)的金屬作陰極時(shí),電子注入勢壘高從而成為少子,導(dǎo)致復(fù)合區(qū)位置靠近陰極并與有機(jī)金屬界面部分交疊。交疊區(qū)金屬原子的高原子序數(shù)會(huì)產(chǎn)生強(qiáng)的SOC作用,單重態(tài)的e-h對向三重態(tài)轉(zhuǎn)換,從而減弱發(fā)光。而外磁場抑制少子的遷移率,進(jìn)一步提高了e-h對復(fù)合區(qū)與有機(jī)金屬交界面重疊程度,發(fā)光進(jìn)一步減弱,最終導(dǎo)致MEL在高場出現(xiàn)明顯下降。在第4章中,為了弄清楚三重態(tài)激子型e-h對(T)與載流子(C)的相互作用(triplet-charge interaction,TCI)的磁電導(dǎo)的本源,我們用空穴遷移率高的紅熒烯(rubrene)代替第三章中電子遷移率高的Alq_3作為活躍層進(jìn)行有機(jī)-金屬界面修飾,使e-h對復(fù)合區(qū)靠近金屬電極。再通過改變電極來調(diào)控C,通過溫度和磁場來調(diào)控rubrene器件中STT和TTA的能量共振的方向,改變STT和TTA從而調(diào)制T。最后測量并分析器件的MEL和MC。結(jié)果發(fā)現(xiàn)MEL不受電極修飾的影響,但Al電極rubrene器件的MC表現(xiàn)了隨磁場增加單調(diào)減小的特征曲線。這種負(fù)的MC與其它金屬電極器件的先負(fù)后正的MC特征明顯不同。我們認(rèn)為,Al電極器件這種負(fù)的MC不應(yīng)該是T激子與過量空穴通過解離或者散射通道的TCI引起的,而是T與陷阱中的束縛電子通過TCI的去陷阱(T+C_t→S_0+C)通道淬滅直接受外磁場抑制引起的。另外,載流子注入較為平衡的Li F/Al和Ca電極器件的MC比Al電極器件的小了1個(gè)量級,且隨磁場的增加先減小后增大,這并非是因?yàn)槠胶庾⑷肫骷䞍?nèi)的TCI弱,而是由于器件內(nèi)rubrene功能層中的陷阱容易被電子占滿,TCI去陷阱淬滅通道和陷阱捕獲淬滅通道對電流的影響變低。因此,載流子陷阱在TCI的磁效應(yīng)中具有重要地位。在上一章節(jié)中,我們是通過有機(jī)-金屬界面修飾,發(fā)現(xiàn)在rubrene中本身自帶的缺陷作為載流子陷阱是TCA混合導(dǎo)致MC的本質(zhì)原因。在第5章中,我們重點(diǎn)討論人為在活躍層中引入陷阱,來研究陷阱參與的e-h對的自旋混合過程的MC和MEL的特征。為此,我們制備了兩種類型的OLED器件。第1種是基于蒽晶體的OLED,采用分子束蒸發(fā)的方法制備蒽的多晶,引入結(jié)構(gòu)缺陷,使得單、三重態(tài)e-h對和極化子都被缺陷束縛。為了簡單它們分別表示為S_1_t,T1_t和P_t。再加上自由的三重態(tài)e-h對(T)和極化子(P),器件內(nèi)實(shí)現(xiàn)了T_tTA,TPI,TP_tI和T_tPI共存。研究器件的MEL和MC,特別是通過Lorentzian經(jīng)驗(yàn)公式擬合發(fā)現(xiàn),rubrene型OLED中有陷阱束縛的e-h對MC的貢獻(xiàn)值很小,不是因?yàn)槭`態(tài)不能產(chǎn)生磁電導(dǎo),而是由于TP_tI和T_tPI導(dǎo)致的MC符號相反,線寬(飽和磁場)相近,當(dāng)兩者共存時(shí)相互抵消的結(jié)果。這與第四章的結(jié)論一致,即束縛態(tài)的e-h對和極化子在TCA這一自旋混合中發(fā)揮重要作用,從而大大影響器件的MC。這一發(fā)現(xiàn),豐富了我們對束縛態(tài)參與的e-h對和極化子的自旋混合的認(rèn)識(shí)。同時(shí),它們的MC特征也可以作為指紋,幫助我們分析有機(jī)器件中是否有束縛態(tài)的e-h對和極化子進(jìn)行自旋混合。第2種是通過向聚合物SY-PPV摻入四氧化三鐵納米顆粒的辦法引入非輻射陷阱,并對器件通大電流進(jìn)行老化處理,從而分析大量陷阱的磁效應(yīng)。結(jié)果發(fā)現(xiàn),MEL的線型特征在摻雜前后發(fā)生了巨大改變:沒有摻雜時(shí),MEL表現(xiàn)為隨磁場單調(diào)上升再飽和的ISC特征。摻雜后,發(fā)光減弱,漏電流很大,但大電流處理前,MEL線型與純的SY-PPV器件相似。這些器件進(jìn)行大電流老化處理后,表現(xiàn)為隨磁場直接下降的負(fù)的MEL線型。據(jù)我們所知,這種MEL線型在大電流處理前后由正變負(fù),截然相反的情況從未報(bào)道過。經(jīng)原子力顯微鏡(AFM)掃描發(fā)現(xiàn),SY-PPV層明顯出現(xiàn)了高溫結(jié)晶導(dǎo)致的結(jié)構(gòu)陷阱。這些結(jié)果表明,陷阱在MEL中也發(fā)揮了重要作用,它們甚至?xí)淖兗ぷ有蚭-h對自旋混合的方向,導(dǎo)致完全相反的磁效應(yīng)。在第6章內(nèi)容中,我們以MEL和MC作為指紋,來分析分子間距對激子型e-h對自旋混合的方向的調(diào)控。我們以rubrene為對象,通過摻雜把它引入到具有較高三重態(tài)的磷光主體材料m CP中。通過改變摻雜濃度的辦法來調(diào)控分子間距d,最終在室溫下實(shí)現(xiàn)對e-h對自旋混合的方向的調(diào)控,即隨著rubrene的分子間距d由1.8 nm增大到5.0 nm,器件內(nèi)部的自旋混合過程實(shí)現(xiàn)了由STT向TTA轉(zhuǎn)換。由于STT過程消耗S_1降低熒光效率,而TTA過程卻產(chǎn)生額外的單重態(tài)激子S_1增強(qiáng)OLED熒光效率。因此,這項(xiàng)工作為我們提供了一個(gè)更有前景的途徑去提升室溫條件下OLED工作效率。另外,在這一章節(jié)中,我們基于Merrifield有關(guān)TTA引起MEL變化的理論模型,還給出了利用高場范圍MEL下降量估算TTA和STT相對強(qiáng)弱的公式,為用MEL量化OLED內(nèi)e-h對間的自旋混合過程提供一個(gè)思路。
[Abstract]:Organic electroluminescence (electroluminescence, EL) devices are organic semiconductor devices using organic materials as active layers and irradiated by external electric field, also known as organic light-emitting diodes (organic light-emitting diode, OLED). In 1987, the electroluminescence of sandwich type organic double layer films was invented by Deng Qingyun (C.W.Tang) blogger. Organic electroluminescent materials and devices have been widely studied and made great progress. The use of organic materials as electronic devices has many advantages, such as simple preparation and chemical regulation, which can be used to make flexible and transparent devices. In addition to OLED, organic solar cells (OSC) and organic spin can be used to produce organic spin. Valve (OSV), an airport effect transistor (OFET). In the past more than 20 years, these organic semiconductor devices have developed rapidly and have made great progress. It has also produced a new discipline, organic electronics. It is a kind of Chemistry (such as organic chemistry, photochemistry and polymer chemistry), and Physics (interface physics, solid physics, semi conductance). Body physics and the process of electron transfer in organic materials and devices, spin transport and electron hole pair (E-H pair) spin mixing. The working principles of organic semiconductor devices in organic electronics and the knowledge of internal micromechanisms can not only help us to understand the properties of organic semiconductor devices, but also optimize the organic matter for us. However, the organic semiconductor materials based on the hydrocarbon are obviously different from the traditional inorganic semiconductor materials in terms of electronic structure, electron transport, carrier mobility and so on. We can not study them completely according to the methods of inorganic semiconductors. For example, the internal mechanism is not perfect. For example In organic semiconductor devices, the positive and negative polarons are composed of the positive and negative polarons of the E-H pair, which influences and converts through the spin mixing, which has an important effect on the performance of the device. The spin related mixing process involved is not fully understood, and the points of view are different or even conflicting. This requires us to carry out the spin mixing process of E-H. There are many methods for the spin mixing process of E-H. The commonly used method is to measure the absorption spectra and emission spectra, transient spectra, luminescence voltage current (B-I-V) characteristic curves of organic devices and so on. According to the needs, the method of adjusting the structure of the device, measuring the temperature and bias voltage and even changing the functional layer, is used to regulate and control the mixing. However, some spin mixing processes are difficult to distinguish by these methods, such as the three heavy state exciton annihilation (TTA) and the anti series channeling (RISC), which are similar to the transient spectra of the delayed fluorescence, and can not be distinguished by the B-I-V curve. Fortunately, the organic semiconductors are semi conductors. Under the effect of applied magnetic field, the light, current and even spectrum of the body will change correspondingly, and this change is often a function of the magnetic field. We call it the organic magnetic field effect (OMFE). It mainly includes the magnetoluminescent effect (MEL) and the magnetic conductivity effect (MC). The different spin mixing process often has different MEL and MC characteristic curves, These curves can be used as the identity labels or fingerprints of E-H's spin mixing process, providing us with a non-contact means of efficient analysis of the internal mechanism of organic semiconductor devices. For example, because the above mentioned TTA and RISC MEL fingerprints are obviously different, it can be easily distinguished by magnetic efficiency. At present, people have already been in OSC, OFET, OSV. Magnetic effects are found in both OLED and OLED, but the main magnetic effects of the first 3 devices are MC. in OLED, the hole h and the electron e meet to form E-H pairs under the electric field Coulomb force. These E-H pairs at different molecules are polaron pairs and the same molecule is a exciton. The spin rule is determined by the single, the three heavy E-H pair is only 25 of the 1:3. fluorescent device. The% singlet exciton type E-H pair contributes to the luminescence, and the 75% of the three heavy state E-H pair is spin forbidden. Therefore, the lifetime of the three state E-H pair can reach 10~ (-6) to 10~2 seconds, much larger than the 10~ (-9) second of the single state E-H, so that the three heavy E-H pairs have long enough time with other E-H pairs and carriers. The process of spin mixing. These spin mixing processes include intersystem channeling (ISC) and single state exciton splitting (STT); and two T excitons producing 1 S excitons through annihilation (TTA), and the interaction between T and carrier (C) or polaron (P). They change the proportion of the single, three state E-H pairs and thus the device's hair. Both light and electric current have an important effect. The external magnetic field, by inhibiting these processes, reversely changes the light and current of the device, thus producing MEL and MC.. We can study the characteristics of these mixing and their effects on the performance of the devices simultaneously through the characteristics of MEL and MC. At the same time, the structure, temperature, interface modification and doping of the device are used. In order to regulate these spin mixing, we can also regulate the magnetic effects such as MEL and MC to achieve specific functional devices, such as organic magnetic sensing. Therefore, the OLED study of E-H and its spin mixing with the polaron will be more advantageous than other organic semiconductor devices. This paper uses OLED devices as the research object, by changing electricity. The sub transmission material is the electrode of the active layer and its evaporation method to modify the organic metal interface. The replacement of the hole transmission material is the electrode of the active layer to regulate the electron injection and the number of defects. The Fe_3O_4 impurities or structural defects are introduced into the organic active layer, and the spin mixing process in the device is regulated. The magnetic effect characteristics of different mixing processes are analyzed by means of spectral and I-B-V curves at different temperatures, and the fingerprint Library of the spin mixing process is perfected. Finally, using the known fingerprint characteristics of the spin mixing process, the possible spin mixing process in the device is analyzed and quantized, and the three heavy state e is proposed by changing the interval between the molecules. The specific content of -h is divided into the following chapters: the first chapter introduces the basic concepts related to the basic concepts of organic spintronics and the basic knowledge of the research content. In particular, the formation process of E-H in OLED, the types of spin mixing with other excitons or electric charges, and the interaction between them, are interacted with each other. Types and related microscopic models and mechanisms, such as hyperfine interaction model (HFI), spin orbit coupling mechanism (SOC), "delta G" mechanism, three heavy exciton annihilation (TTA model), single state exciton dissociation (STT), bipolar submodel (Bipolaron), three heavy state electric charge (TCA), etc. "the second chapter introduces the method of preparing OLED in this experimental group, in detail. Test of process and sample. The vacuum evaporation method of organic layer and metal electrode, spectral analysis, magnetic effect analysis and other measurement analysis methods and techniques are emphasized. In the third chapter, the typical electronic transmission and luminescent material Alq_3 is selected as the active layer, and the OLED device with the structure of ITO/Cu Pc/NPB /Alq_3/ metal electrode is prepared. We use Al, Cu, Au and Li F/Al electrodes to change the work function and the atomic number of the electrode, and modify the organic metal interface by changing the vacuum evaporation method (molecular beam deposition, thermal resistance evaporation and electronic Shu Zhengfa) by changing the vacuum evaporation method of the metal electrode. Finally, the control of the self spin mixing process of E-H in the device is realized. And then the series is measured by measuring this series. The control results were analyzed by MEL and MC in the temperature range of 20 K~300 K. The experimental results showed that when the work function of vapour plating was high and the atomic number was large, the MEL of the device decreased obviously in the high field, and this descent could not be used by the E-H with high field drop, such as TTA, TCA, double polarization. A new model is proposed to explain the high field drop: the interface modification of the organic metal interface can change the position of the E-H to the complex region. When the metal as the cathode of the high power function, the electron injection barrier is high and thus becomes a minority, leading to the overlapping of the composite location by the near cathode and with the interface part of the organic metal. The high atomic number of the metal atom in the region will produce a strong SOC effect, and the E-H of the single heavy state converts to the three heavy state, thereby reducing the luminescence. The external magnetic field inhibits the mobility of the minority, and further improves the degree of overlap between the E-H and the interface of the organic metal. The luminescence is further weakened, which eventually leads to a significant decline in the high field of MEL. In the fourth chapter In order to find out the origin of the magnetic conductance of the three state exciton type E-H pair (T) and carrier (C) interaction (triplet-charge interaction, TCI), we use the high hole mobility of the red fluorenes (rubrene) instead of the Alq_3 in the third chapter as the active layer to carry out the organic metal interface modification, so that E-H is close to the metal electricity in the complex region. By changing the electrode to regulate the C, the direction of the energy resonance of STT and TTA in the rubrene device is regulated by the temperature and magnetic field, the STT and TTA are changed and the T. is modulated and the MEL and MC. results of the device are analyzed to find that MEL is not affected by the electrode modification, but the Al electrode rubrene parts show the monotonous decrease with the increase of the magnetic field. The negative MC is obviously different from the negative positive MC characteristics of other metal electrodes. We think that the negative MC of the Al electrode should not be caused by the TCI of the T exciton and the excess hole through the dissociation or scattering channel, but the quenching of the T and the bound electrons in the trap (T+C_t to S_0+C) through the TCI. It is caused by external magnetic field suppression. In addition, the MC of the carrier injected into the more balanced Li F/Al and Ca electrode devices is 1 orders of magnitude smaller than the Al electrode device, and decreases with the increase of the magnetic field first and then increases. This is not because the TCI in the balanced injection device is weak, but because the traps in the rubrene function layer are easily occupied by the electrons in the device, TCI goes. The effect of trap quenching channel and trap capture quenching channel on the current is reduced. Therefore, the carrier trap plays an important role in the magnetic effect of TCI. In the last chapter, we found that the inherent defect of the carrier trap in rubrene is the essential reason for the TCA mixing to lead to the MC. In the fifth chapter, the carrier trap is the carrier trap. We focus on the introduction of traps in the active layer to study the characteristics of MC and MEL in the spin mixing process of E-H pairs involved in the trap. To this end, we have prepared two types of OLED devices. The first is based on the OLED of anthracene crystal, the polycrystalline anthracene is prepared by molecular beam evaporation, and the structural defects are introduced to make the single, three heavy E-H. Both the pair and the polaron are bound by the defects. In order to simply be expressed as S_1_t, T1_t and P_t. with the free three heavy E-H pair (T) and the polaron (P), T_tTA, TPI, TP_tI and T_tPI are realized in the device. The contribution value of MC is very small, not because the bound state does not produce magnetic conductance, but is the result of the opposite of the MC symbol caused by the TP_tI and T_tPI, the line width (saturated magnetic field) and the mutual counteraction when both coexist. This is in agreement with the conclusion of the fourth chapter that the E-H pair in the bound state and the polaron play an important role in the spin mixing of TCA. The discovery of MC. in large impact devices enriches our understanding of the spin mixing of E-H pairs and polarons involved in bound states. At the same time, their MC characteristics can also be used as fingerprints to help us analyze the spin mixing of E-H pairs with bound states in the machine parts and the polarons. The second is by adding four oxidation to the polymer SY-PPV. The non radiation trap was introduced into the three iron nanoparticles and the magnetic effects of the large current were analyzed. The results showed that the linear features of MEL changed dramatically before and after doping. When the doping was unadulterated, the MEL showed a ISC characteristic with the monotonous rise of the magnetic field. After doping, the luminescence was weakened and the leakage was lost. The flow is very large, but the MEL line is similar to the pure SY-PPV device before large current treatment.
【學(xué)位授予單位】：西南大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2016
【分類號】：TN383.1
，

本文編號：2018090