Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-27T02:17:54.507Z Has data issue: false hasContentIssue false

Combinatorial Fabrication and Studies of Small Molecular Organic Light-Emitting

Published online by Cambridge University Press:  01 February 2011

Devices G. Li
Affiliation:
Department of Physics and Astronomy Iowa Sate University, Ames, Iowa 50011
L. Zou
Affiliation:
Department of Physics and Astronomy Iowa Sate University, Ames, Iowa 50011
K. O. Cheon
Affiliation:
Department of Physics and Astronomy Iowa Sate University, Ames, Iowa 50011
J. Shinar
Affiliation:
Ames Laboratory - USDOE, Ames, Iowa 50011
Get access

Abstract

Various combinatorial matrix arrays of UV-violet, white, and blue-to-red organic light-emitting devices (OLEDs), fabricated using a sliding shutter technique, are described. In the UV-violet devices, which contain a UV-violet emitting layer of 4,4′-bis(9-carbazolyl) biphenyl (CBP), the optimal radiance R and external quantum efficiency ηext were determined with respect to the thicknesses of the hole transporting layers. In the blue-to-red devices, which contained a blue-emitting layer of 4,4′-bis(2,2′-diphenyl-vinyl) -1,1′-biphenyl (DPVBi) and a red-emitting 5 wt.% dye-doped guest-host layer, the color of the devices evolved continuously from blue to red as the thickness of the doped layer increased from 0 to 35 Å. The (nominal) 2 Å-thick doped layer device exhibited the highest brightness L ∼ 120 Cd/m2 and external quantum efficiency ηext ∼4.4 % at a current density of 1 mA/cm2. In the white OLEDs, which were similar to the blue-to-red devices but with lightly doped emission layer, the highest brightness Lmax was over 74,000 Cd/m2; in all devices Lmax exceeded 50,000 Cd/m2. The maximum efficiencies were 11.0 Cd/A, 5.96 lm/W and 4.6% at 5.8 V, 0.6 mA/cm2, and 68 Cd/m2 in a 0.25 wt.%, 2 nm-thick doped layer device.

Type
Research Article
Copyright
Copyright © Materials Research Society 2004

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Organic Light Emitting Materials and Devices III, edited by Kafafi, Z. H., SPIE Conf. Proc. 3797 (SPIE, Bellingham, WA, 1999);Google Scholar
Johnson, M.T. and Sampel, A., Information Display 16 (2), 12 (2000).Google Scholar
2. Schmitz, C., Thelakkat, M., and Schmidt, H. W., Adv. Mater. 11, 82 (1999);Google Scholar
Shmitz, C., Psch, P., Thelakkat, M., and Schmidt, H. W., Phys. Chem. Chem. Phys. 1, 1777 (1999).Google Scholar
3. Zou, L., Savvate'ev, V., Booher, J., Kim, C.-H., and Shinar, J., Appl. Phys. Lett. 79, 2282 (2001).Google Scholar
4. Cheon, K. O. and Shinar, J., Appl. Phys. Lett. 83, 2073 (2003).Google Scholar
5. Li, G. and Shinar, J., Appl. Phys. Lett. 83, 5359 (2003).Google Scholar
6. Li, F., Tang, H., Shinar, J., Resto, O., and Weisz, S. Z., Appl. Phys. Lett. 70, 2741 (1997).Google Scholar
7. Becker, H., Burns, S. E., and Friend, R. H., Phys. Rev. B 56, 1893 (1997).Google Scholar
8. Bulovic, V., Shoustikov, A., Baldo, M. A., Bose, E., Kozlov, V. G., Thompson, M. E. and Forrest, S. R., Chem. Phys. Lett. 287, 455 (1998).Google Scholar
9. Baldo, M. A., Soos, Z. G., and Forrest, S. R., Chem. Phys. Lett. 347, 297 (2001).Google Scholar
10. Deshpande, R. S., Bulovic, V., and Forrest, S. R., Appl. Phys. Lett. 75, 888 (1999).Google Scholar
11. Chuen, C. H. and Tao, Y. T., Appl. Phys. Lett. 81, 4499 (2002).Google Scholar