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Indium-gallium-zinc oxide thin film transistor(IGZO-TFT) was fabricated using N2O plasma treated SiNx film as gate insulator and room-temperature deposited IGZO film as active layer.Comparing with the conventional IGZO-TFT,the saturation mobility increased from 4.5 to 8.1 cm2·V-1·s-1,threshold voltage reduced from 11.5 to 3.2 V,threshold swing varied from 1.25 to 0.9 V/dec.The trap states in the N2O plasma treated IGZO-TFT is obviously smaller than that in the conventional IGZO-TFT.Our results indicate that using N2O plasma treated SiNx film as gate insulator is an effective approach for improving IGZO-TFT performance.

Efficient inverted top-emitting organic light-emitting diode(ITOLED) using a thin Cs2CO3 layer modified Al as the reflective bottom cathode is demonstrated.With tris-(8-hydroxy-quinoline) aluminum(Alq3) as emitting layer and MoO3/Ag as semitransparent anode,the Al/Cs2CO3 based ITOLED shows a tune-on voltage of 3.6 V,luminance efficiency of 9.8 cd/A and 3.4 lm/W,which are much better than those(4.2 V,8.6 cd/A,2.85 lm/W) obtained from Mg∶Ag based ITOLED and those(5 V,5.5 cd/A,1.57 lm/W) obtained from bare Al based ITOLED.Electron-only devices research shows that a stronger electron-injection is obtained from Al/Cs2CO3 than Mg∶Ag and Al,which is attributed to the lower work function of Al/Cs2CO3 than Mg∶Ag and Al.The good performance of Al/Cs2CO3 based ITOLED is attributed to the efficient electron injection from the Al/Cs2CO3 cathode as well as a microcavity effect.

The bottom gate thin-film transistors(TFTs) with un-annealed and annealed ZnO film as a channel layer were fabricated.Compared with the un-annealed device,the performance of the device with annealed ZnO had been improved.The saturation mobility increased from 2.3 to 3.12 cm2/(V·s),the threshold voltage reduced from 20.8 to 9.9 V,the threshold swing varied from 2.6 to 1.9 V/dec,and the threshold voltage shifted from 8.0 to 3.4 V after applying a gate bias stress of 25 V for 3 600 s.The experimental results indicate that using annealed ZnO film as channel layer is an effective approach for improving ZnO-based TFT performance and bias stress stability.

Bottom-gate ZnO thin-film transistors(ZnO-TFTs) were fabricated with Ta2O5 film as the insulator.Ta2O5 film was grown by the radio-frequency magnetron sputtering at room temperature.The thickness of the Ta2O5 layers were 100,85,60,40 nm separately.The effect of the thickness on the performance of the ZnO-TFTs was studied.With the thickness of the insulator decreased from 100,85,60 nm to 40 nm,the field effect mobility increased from 50.5,59.3,63.8 to 71.2 cm2/V·s.The surface morphology of the Ta2O5 films were checked by the atomic force microscope,which showed that the root mean square(RMS) of the Ta2O5 films roughness decreases with decreasing the insulator thickness.The Ion/Ioff ratio and the threshold voltage are changed with the insulator thickness.