Organic light emitting diodes (OLEDs) incorporating an n-doping transport layer comprised of 8-hydroxy-quin- olinato lithium (Liq) doped into 4' 7- diphyenyl-1,10-phenanthroline (BPhen) as ETL and a p-doping tr...Organic light emitting diodes (OLEDs) incorporating an n-doping transport layer comprised of 8-hydroxy-quin- olinato lithium (Liq) doped into 4' 7- diphyenyl-1,10-phenanthroline (BPhen) as ETL and a p-doping transport layer that includes tetrafluro-tetracyano-quinodimethane (F4- TCNQ) doped into 4,4′, 4″-tris (3-methylphenylphenylamono) triphe- nylamine (m-MTDATA) are demonstrated. In order to examine the improvement in the conductivity of transport layers, hole-only and electron-only devices are fabricated. The current and power efficiency Of organic light-emitting diodes are improved significantly after introducing an n-doping (BPhen:33wt% Liq) layer as an electron transport layer (ETL) and a p-doping layer composed of m-MTDATA and F4- TCNQ as a hole transport layer (HTL). Compared with the control device (without doping) , the current efficiency and power efficiency of the most efficient device (device C) are enhanced by approximately 51% and 89% ,respectively, while driving voltage is reduced by 29%. This improvement is attributed to the improved conductivity of the transport layers that leads to efficient charge balance in the emission zone.展开更多
An organic thin-film transistor (OTFT) with an OTS/SiO2 bilayer gate insulator and a MoO3/AI electrode configuration between gate insulator and source/drain electrodes has been investigated. A thermally grown SiO2 l...An organic thin-film transistor (OTFT) with an OTS/SiO2 bilayer gate insulator and a MoO3/AI electrode configuration between gate insulator and source/drain electrodes has been investigated. A thermally grown SiO2 layer is used as the OTFT gate dielectric and copper phthalocyanine(CuPc) is used as an active layer. This OTS/SiO2 bilayer gate insulator configuration increases the field-effect mobility, reduces the threshold voltage, and improves the on/off ratio simultaneously. The device with a MoO3/Al electrode has shown similar Ids compared to the device with an Au electrode at the same gate voltage. Our results indicate that using a double-layer of electrodes and a double-layer of insulators is an effective way to improve OTFT performance.展开更多
The electron mobilities of 4, 7-diphenyl-1, 10-phenanthroline (BPhen) doped 8-hydroxyquinolinatolithium (Liq) at various thicknesses (50-300 nm) have been estimated by using space-charge-limited current measurem...The electron mobilities of 4, 7-diphenyl-1, 10-phenanthroline (BPhen) doped 8-hydroxyquinolinatolithium (Liq) at various thicknesses (50-300 nm) have been estimated by using space-charge-limited current measurements. It is observed that the electron mobility of 33 wt% Liq doped BPhen approaches its true value when the thickness is more than 200 rim. The electron mobility of 33 wt% Liq doped BPhen at 300 nm is found to be -5.2 × 10^-3 cm^2/(V.s) (at 0.3 MV/cm) with weak dependence on electric field, which is about one order of magnitude higher than that of pristine BPhen (3.4 × 10^-4 cm^2/(V.s)) measured by SCLC. For the typical thickness of organic light-emitting devices, the electron mobility of doped BPhen is also investigated.展开更多
文摘Organic light emitting diodes (OLEDs) incorporating an n-doping transport layer comprised of 8-hydroxy-quin- olinato lithium (Liq) doped into 4' 7- diphyenyl-1,10-phenanthroline (BPhen) as ETL and a p-doping transport layer that includes tetrafluro-tetracyano-quinodimethane (F4- TCNQ) doped into 4,4′, 4″-tris (3-methylphenylphenylamono) triphe- nylamine (m-MTDATA) are demonstrated. In order to examine the improvement in the conductivity of transport layers, hole-only and electron-only devices are fabricated. The current and power efficiency Of organic light-emitting diodes are improved significantly after introducing an n-doping (BPhen:33wt% Liq) layer as an electron transport layer (ETL) and a p-doping layer composed of m-MTDATA and F4- TCNQ as a hole transport layer (HTL). Compared with the control device (without doping) , the current efficiency and power efficiency of the most efficient device (device C) are enhanced by approximately 51% and 89% ,respectively, while driving voltage is reduced by 29%. This improvement is attributed to the improved conductivity of the transport layers that leads to efficient charge balance in the emission zone.
文摘An organic thin-film transistor (OTFT) with an OTS/SiO2 bilayer gate insulator and a MoO3/AI electrode configuration between gate insulator and source/drain electrodes has been investigated. A thermally grown SiO2 layer is used as the OTFT gate dielectric and copper phthalocyanine(CuPc) is used as an active layer. This OTS/SiO2 bilayer gate insulator configuration increases the field-effect mobility, reduces the threshold voltage, and improves the on/off ratio simultaneously. The device with a MoO3/Al electrode has shown similar Ids compared to the device with an Au electrode at the same gate voltage. Our results indicate that using a double-layer of electrodes and a double-layer of insulators is an effective way to improve OTFT performance.
基金Project supported by the National Natural Science Foundation of China (Nos.60477014,60577041,60776040,60777018)the National High Technology Research and Development Program of China (No.2008AA03A336)
文摘The electron mobilities of 4, 7-diphenyl-1, 10-phenanthroline (BPhen) doped 8-hydroxyquinolinatolithium (Liq) at various thicknesses (50-300 nm) have been estimated by using space-charge-limited current measurements. It is observed that the electron mobility of 33 wt% Liq doped BPhen approaches its true value when the thickness is more than 200 rim. The electron mobility of 33 wt% Liq doped BPhen at 300 nm is found to be -5.2 × 10^-3 cm^2/(V.s) (at 0.3 MV/cm) with weak dependence on electric field, which is about one order of magnitude higher than that of pristine BPhen (3.4 × 10^-4 cm^2/(V.s)) measured by SCLC. For the typical thickness of organic light-emitting devices, the electron mobility of doped BPhen is also investigated.