Browse > Article
http://dx.doi.org/10.4313/JKEM.2009.22.11.956

Luminescent Properties of OLEO Devices with Various Substrate Temperatures  

Kim, Jung-Taek (대진대학교 전자공학과)
Paek, Kyeong-Kap (대진대학교 전자공학과)
Ju, Sung-Hoo (대진대학교 신소재공학과)
Publication Information
Journal of the Korean Institute of Electrical and Electronic Material Engineers / v.22, no.11, 2009 , pp. 956-960 More about this Journal
Abstract
The characteristics of organic films can be affected by the temperature of evaporation source because the temperature of evaporation source has an effect on substrate temperature during OLED fabrication process using the thermal evaporation. To investigate the characteristics of OLED devices fabricated by using thermally damaged organic films, I-V-L and half life-time in OLED devices fabricated with various substrate temperatures were measured. During emission layer(EML) evaporation, OLED devices with a structure of ITO(100 nm)/ELM200(50 nm)/NPB(30 nm)/$Alq_3$(55 nm)/LiF(0.7 nm)/Al(100 nm) were fabricated at various substrate temperatures(room temperature, $30^{\circ}C$, $40^{\circ}C$, and $50^{\circ}C$). The characteristics of current density and luminance versus applied voltage in OLED devices fabricated shows that many electrical currents flowed and high brightness appeared at low voltage, but that the lifetime of OLED devices dropped suddenly. This phenomenon explained that the crystallization of $Alq_3$ thin film appeared owing to the substrate heating during evaporation.
Keywords
Evaporation; I-V-L; Lifetime; OLED; Temperature;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
연도 인용수 순위
1 A. B. Djurisic, T. W. Lau, C. Y. Kwong, L. S. M. Lam, and W. K. Chan., 'Evolution of optical properties of tris(8-hydroxyquinoline) aluminum $(Alq_3)$ with atmosphere exposure', Proc. SPIE, Vol. 4800, p. 200, 2003   DOI
2 A. B. Djuri$\check{s}$i$\dot{c}$, C. Y. Kwong, W. L. Guo, T. W. Lau, E. H. Li, Z. T. Liu, H. S. Kwok, L. S. M. Lam, and W. K. Chan, 'Spectroscopic ellipsometry of the optical functions of tris(8-hydroxyquinoline) aluminum $(Alq_3)$', Thin Solid Films, Vol. 416, No. 1-2, p. 233, 2002   DOI   ScienceOn
3 C. Y. Kwong, A. B. Djurisic, V. A. L. Roy, P. T. Lai, and W. K. Chan, 'Influence of the substrate temperature to the performance of tris(8-hydroxyquinoline) aluminum based organic light emitting diodes', Thin Solid Films, Vol. 458, No. 1-2, p. 281, 2004   DOI   ScienceOn
4 F. Papadimitrakopoulos, X.-M. Zhang, and K. A. Higginson, 'Chemical and morphological stability of aluminum tris(8-hydroxyquinoline) $(Alq_3)$: Effects in light-emitting devices', IEEE J. Sel. Top. Quantum Electron., Vol. 4, No. 1, p. 49, 1998   DOI   ScienceOn
5 C. W. Tang and S. A. VanSlyke, 'Organic electroluminescent diodes', Appl. Phys. Lett., Vol. 51, No. 12, p. 913, 1987   DOI
6 H. Aziz, Z. Popovic, S. Xie, A.-M. Hor, N.-X. Hu, C. Tripp, and G. Xu, 'Humidity-induced crystallization of tris(8- hydroxyquinoline) aluminum layers in organic light-emitting devices', Appl. Phys. Lett., Vol. 72, No. 7, p. 756, 1998   DOI   ScienceOn
7 박현식, 최영선, 김부웅, 류봉기, 'Tris(8- hydroxyquinoline) aluminum 박막의 수분과 온도에 의한 모폴로지 변화', 공업화학, 14권, 7호, p. 915, 2003
8 D. Kolosov, D. S. English, V. Bulovic, P. F. Barbara, S. R. Forrest, and M. E. Thompson, 'Direct observation of structural changes in organic light emitting devices during degradation', J. Appl. Phys., Vol. 90, No. 7, p. 3242, 2001   DOI   ScienceOn
9 D. E. Mentley, 'State of flat-panel display technology and future trends', Proc. IEEE, Vol. 90, No. 4, p. 453, 2002.   DOI   ScienceOn
10 이봉섭, 고신위, 박종억, 백용구, 양재웅, 백경갑, 주성후, '정공주입층에 따른 OLED 소자의 발광 특성', 전기전자재료학회논문지, 21권, 6호, p. 562, 2008   DOI
11 P. E. Burrows, V. Bulovic, S. R. Forrest, L. S. Sapochak, D. M. McCarty, and M. E. Thompson, 'Reliability and degradation of organic light emitting devices', Appl. Phys. Lett., Vol. 65, No. 23, p. 2922, 1994   DOI   ScienceOn
12 Y.-F. Liew, H. Aziz, N.-X. Hu, H. Chan, G. Xu, and Z. Popovic, 'Investigation of the sites of dark spots in organic light-emitting devices', Appl. Phys. Lett., Vol. 77, No. 17, p. 2650, 2000   DOI   ScienceOn