Research Article
The Selection of Anode and Cathode Materials for Top Emission Organic Light-Emitting Diodes
Table 4
A detailed discussion of resistance, voltage, and current of anode side, an organic layer, and cathode side, respectively, in TE-OLED.
| | Device structure | Total | Anode side | Organic layer | Cathode side Alq/LiF/Al | I-L-V results |
| Ag/NPB
w/o MoO3 | = | (high) | | (low) | No emitting
No h+ crt
Low crt | | (due to high barrier) | | | | = | (high, ) | | (low) | | = | (low) | | (low) | Ag/MoO3
vs
w/o MoO3 | = | (low) | | (low) | Emitting, total current increased | | 1. Ag/MoO3/NPB barrier decreased.
2. IV curves like ohmic contact.
3. Ag/MoO3 interface may have defects. | | | | = | (decreased a little) | | | | (transferred to cathode) | | (increased) | | = | (high, ) | | (increased) | Ag/Au/MoO3
vs
Ag/MoO3 | = | (increased) | | (low) | Luminance increased, total current decreased | | 1. Schottky barrier formed and energy level for h+ injection likes a gradual ladder.
2. Ag/MoO3 interface improved. | | | | = | | | | | = | (decreased more)
e/h current more balanced | | (increased a little) | Ag/Au/MoO3/.../TPBi/
LiF/Al | = | | | | Total current increased
Luminance increased | | | Decreased due to TPBi with higher e mobility. | | | = | | | | | = | | | (increased)
e/h crt more balanced |
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