Improved Fabrication Process for Enhancing Light Emission in Single-Layer Organic Light-Emitting Devices Doped with Organic Salt

Abstract

We investigated an improved method for enhancing light emission in single-layer organic light-emitting devices (OLEDs) stimulated by thermal and electrical annealing. In this study, we introduced fluorescent single-layer OLEDs doped with organic salt, tetrabutylammonium tetrafluoroborate (Bu 4 NBF 4 ). The annealing process consisted of simultaneously treated by thermal and electrical annealing in a noble gas environment filled with argon gas. Comparing with nonannealed OLEDs, we clearly observed homogeneous and ehanced electroluminescent (EL) emission over the entire active area with fast response and improved efficiency from annealed OLEDs. According to these improved EL characteristics, we considerably assumed that these phenomenons leading to the enhanced EL of single-layer OLEDs due to increased and balanced injection of carriers are due to simultaneous annealing, which induces proper adsorption of charged salt ions on the electrode surface.

Effect of Electric Field Treatment on the Performance of Organic Salt Doped Solar Cell

“…Organic and inorganic salt doping approach has also been applied to improve the performance of organic light emitting diode (OLED) [4][5]. Etoh et al reported that the performance of OLED doped with lithium perchlorate (LiClO 4 ) improved with the increase of electric field treatment [5].…”

“…Yang et al suggested that improvement of OLED performance could be achieved by simultaneous thermal and electrical treatment at relatively smaller electric field strength [4]. To the best of our knowledge, the effect of electrical treatment at different voltages on the performance of organic salt doped solar cell has yet to be explored.…”

Effect of Organic Salt Doping on Electron Injection in Single-Layer Polymer Light-Emitting Diodes

“…As another approach, doping of organic or inorganic salt has been known to enhance electron injection in PLEDs by the accumulation of ions near the cathode. [1][2][3][4][5][6] Appropriate biasing an electric field to PLEDs at a certain temperature invokes ions to move the counter electrodes. The base polymer of OLEDs could be poly(N-vinyl carbazole) (PVK), [1][2][3] poly(9,9 0 -dioctylfluorene) (PFO), 4) poly[2-methoxy-5-(2 0 -ethyl-hexyloxy)-1,4-phenylenevinylene] (MEH-PPV), 5) or poly(methyl metacrylate) (PMMA).…”

“…The base polymer of OLEDs could be poly(N-vinyl carbazole) (PVK), [1][2][3] poly(9,9 0 -dioctylfluorene) (PFO), 4) poly[2-methoxy-5-(2 0 -ethyl-hexyloxy)-1,4-phenylenevinylene] (MEH-PPV), 5) or poly(methyl metacrylate) (PMMA). 6) In these studies, the salts utilized were tetra-n-butylammonium tetrafluoroborate (Bu 4 NBF 4 ), lithium bromide (LiBr), or lithium perchlorate (LiClO 4 ).…”