講演抄録/キーワード |
講演名 |
2022-07-29 13:55
[招待講演]光照射成膜によるOLEDモデル素子の電流効率の向上と蓄積電荷の増加 ○田中有弥(群馬大)・田雜友貴・篠原 真・栢口英之・阿部直矢・栗原啓輔・大原正裕・石井久夫(千葉大) |
抄録 |
(和) |
有機発光ダイオード(Organic light-emitting diodes (OLEDs))の一般的な材料であるtris-(8-hydroxyquinolinato) aluminium(Alq3)や1,3,5-tris(1-phenyl-1H-benzimidazole-2-yl)benzene(TPBi)等の極性分子を真空蒸着によって成膜すると,永久双極子が自発的に基板面外方向にわずかに配向し,膜の表面と裏面に正負の分極電荷が生じる.近年この分極電荷が,電荷の注入や蓄積過程に対してだけではなく,OLEDの発光効率や寿命といった素子性能に大きく影響を与えることが明らかになってきた.今後より詳細に分極電荷とデバイス特性の相関を理解するためには,分子の配向制御を行いつつ,素子内の電荷の挙動や素子特性を評価する必要がある.最近になって我々は光を照射しながらTPBiを成膜することで,分極電荷とOLEDモデル素子の電流効率が増加することを見出した.本講演ではそのメカニズムを議論するとともに,自発配向分極を示すOLED材料の新しい応用について紹介する. |
(英) |
When polar molecules such as tris-(8-hydroxyquinolinato)aluminium (Alq3) and 1,3,5-tris(1-phenyl-1H-benzimidazole-2-yl)benzene (TPBi), which are common materials for organic light-emitting diodes (OLEDs), are deposited by vacuum evaporation, the permanent dipoles spontaneously orient outward from the substrate surface. As a result, positive and negative polarization charges are formed on the surface and reverse sides of the film. In recent years, it has been found that the polarization charges affect not only charge injection and accumulation properties but also device performance, such as luminous efficiency and lifetime of the OLED. To understand the correlation between polarization charge and device characteristics in more detail, it is necessary to evaluate the behavior of charge in the device and the device performance while controlling the orientation of polar molecules. Recently, we found that OLED model devices' polarization charge and current efficiency increase when TPBi films are deposited under light irradiation. In this talk, we will discuss the mechanism of the improvement and introduce new applications of organic molecules showing spontaneous oriented polarization. |
キーワード |
(和) |
有機発光ダイオード / 環境発電 / 極性分子 / エレクトレット / 配向分極 / / / |
(英) |
Organic Light-Emitting Diode / Energy Harvesting / Polar Molecule / Electret / Orientation Polarization / / / |
文献情報 |
映情学技報, vol. 46, no. 22, IDY2022-24, pp. 13-16, 2022年7月. |
資料番号 |
IDY2022-24 |
発行日 |
2022-07-22 (IDY) |
ISSN |
Print edition: ISSN 1342-6893 Online edition: ISSN 2424-1970 |
PDFダウンロード |
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