Thin films of N,N'-bis-(3-Naphthyl)-N,N'-biphenyl-(1,1'-biphenyl)-4,4'-diamine (NPB), tris-(8-hydroxyquinoline)-aluminum (Alq(3)) and their blends prepared by spin-coating process were investigated. Experimental results revealed that the NPB films prepared by spin-coating process have smoother surface than that of Alq(3), which was attributed to their different molecular structures. Organic light-emitting devices (OLEDs) with emitting layer prepared by spin-coating the blends of NPB and Alq(3) exhibited a maximum luminance and a current efficiency over 10,000 cd/m(2) and 3.8 cd/A respectively, and when 10-(2-benzothiazolyl)-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H,11H-[1]benzopyrano[6.7,8-ij]quinolizin-11-one was doped in, a current efficiency of 8 cd/A can be obtained. Comparative device performance to the vapor-deposited OLEDs suggested that solution-process could be an alternative route for the fabrication of OLEDs based on Alq(3). (C) 2009 Elsevier B.V. All rights reserved.