Organic light-emitting devices with a mixed layer acting as a hole transport and as an emitting/electron transport layer

ABSTRACTOrganic light-emitting devices (OLEDs) have attracted a lot of attention as a next generation display. In this study, we fabricated the micro-OLEDs by room-temperature curing nanoimprint lithography (RTC-NIL) using diamond molds. The diamond has superior durability and was used as mold material for RTC-NIL. The diamond molds have been fabricated by electron cyclotron resonance (ECR) oxygen ion shower with polysiloxane oxide mask in the electron beam (EB) lithography technology. We fabricated the diamond mold pattern with 10 μm-square dot. The diamond molds have been used to form an insulating layer in micro-OLEDs. The optimum thickness of N,N’-Diphenyl-N,N’-di(m-tolyl)benzidine (TPD) [hole transport layer],Tris(8-quinolinolato)aluminum (Alq3) [electron transport layer] and aluminum (Al) [cathode] were 40 nm, 40 nm and 200 nm, respectively. We succeeded in formation of insulating layer in micro-OLEDs and operation of micro-OLEDs with 10 μm-square-dot by RTC-NIL using diamond molds.

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Bright green organic light-emitting devices having a composite electron transport layer

Microelectronics Journal ◽

10.1016/j.mejo.2006.01.013 ◽

2006 ◽

Vol 37 (9) ◽

pp. 916-918 ◽

Cited By ~ 2

Author(s):

Fangcong Wang ◽

Su Liu ◽

Jianlin Zhou ◽

Shuo Sun ◽

Bingli Qi ◽

...

Keyword(s):

Electron Transport ◽

Transport Layer ◽

Electron Transport Layer ◽

Light Emitting ◽

Light Emitting Devices ◽

Organic Light ◽

Bright Green ◽

Organic Light Emitting Devices

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The Effects of Processing Conditions on the Efficiency and Lifetime of Organic Light Emitting Devices Incorporating a New Oxadiazole Derivative

MRS Proceedings ◽

10.1557/proc-708-bb5.8 ◽

2001 ◽

Vol 708 ◽

Cited By ~ 1

Author(s):

G.Y. Jung ◽

C. Wang ◽

P. Cea ◽

C. Pearson ◽

M.R. Bryce ◽

...

Keyword(s):

Electron Transport ◽

Transport Layer ◽

Electron Transport Layer ◽

Processing Conditions ◽

Applied Bias ◽

Light Emitting ◽

Light Emitting Devices ◽

Organic Light ◽

Operating Lifetime ◽

Organic Light Emitting Devices

ABSTRACTThe effects of processing conditions on the properties of organic light emitting devices (LEDs) based on rubrene-doped poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene] and a new electron transporting material, 2,5-bis[2-(4-tert-butylphenyl)-1,3,4-oxadiazol-5-yl]pyridine, are reported. These dual-layer LEDs exhibited a higher quantum efficiency than observed for structures incorporating the more widely used electron transport compound 1,3-bis[2-(4-tert-butylphenyl)-1,3,4-oxadiazol-5-yl]benzene (OXD-7). However, the as-prepared devices degraded relatively rapidly on storage (10-1 mbar, no applied bias). Thermal annealing of the degraded devices at 160 °C for 30 minutes restored the currents and light outputs close to those measured for fresh devices. The annealed LEDs exhibited a significant increase in their operating lifetime. Lifetime improvements could also be achieved by increasing the deposition rate and thickness of the thermally evaporated aluminium top electrode. These effects are attributed to better adhesion between the aluminium top electrode and the underlying electron transport layer.

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