P-136: Highly Stable Organic Light Emitting Devices with a Uniformly Mixed Hole Transport Layer

Abstract

Highly stable organic light emitting devices can be made by using a uniformly mixed hole transport layer (UM-HTL). Stability of 10doped green device can be greatly improved to 3 times longer than that of the conventional NPB based HTL without impacting on the driving voltage and the color saturation. The half-decay lifetime (t 1/2 ) is 52,000h at an initial brightness of 100 cd/m 2 with an efficiency and Commission Internationale d'Eclairage (CIE x,y ) of 12.9 cd/A and (0.31, 0.64). The lifetime of our device with UM-HTL is also twice longer than that of the best reported in the literature for C-545T doped device using the bipolar transport and emitting layer device structure (BTEL) (24,000h).