Abstract
The influence of vacuum conditions during the deposition of Ca/Ag cathode on the performance of top emission organic light-emitting devices (TEOLEDs) is investigated. The fabricated devices have been characterized by current-voltage (I-V) and electroluminescence (EL) measurements. Low turn-on voltage and high yield of EL are observed if the cathode is deposited in a better background pressure than 2.78 × 10-6 Torr, whereas the deposition of cathode in a poor back ground pressure (<2.78 × 10-6 Torr) leads to device failure. It is argued that the partial oxidation of Ca significantly improves the transparency of the Ca/Ag cathode while remaining conducting, whereas the complete oxidation of Ca (formation of Ca-O bonds) results into device failure.
Original language | English |
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Pages (from-to) | 63-68 |
Number of pages | 6 |
Journal | Synthetic Metals |
Volume | 146 |
Issue number | 1 |
DOIs | |
State | Published - 14 Oct 2004 |
Keywords
- Ca oxidation
- Ca/Ag semitransparent cathode
- Device failure
- Top emission organic light-emitting devices (TEOLEDs)
- Transmittance