热处理对以Al_2O_3为绝缘层的并五苯薄膜晶体管性能的影响

Effect of annealing on organic thin-film transistor based on high-k anodizing Al_2O_3 dielectric

采用阳极氧化法制备了Al_2O_3绝缘材料,并制备了以Al_2O_3为绝缘层的并五苯薄膜晶体管器件(OTFT)。Al_2O_3绝缘层经过10 min 350℃氢热处理后,OTFT迁移率比未经氢热处理的增大近20倍,且阈值电压降到了-7 V。Al_2O_3膜MIS结构电容—电压(C–V)特性的平带电压平移量数据表明,Al_2O_3膜经过热处理后,并五苯半导体与Al_2O_3绝缘体界面处以及绝缘体内缺陷态密度显著地降低,Al_2O_3绝缘层和并五苯半导体层之间的接触得到改善,这使得经热处理Al_2O_3膜的OTFT器件性能得到显著的改善。

Organic thin-film transistors （OTFTs） based on anodizing Al2O3 dielectric are investigated. Al2O3 is treated at 350 ℃ for 10 min under HE atmosphere, and the mobility of the OTFT with Al2O3 gate insulator treated under H2 atmosphere is improve nearly 20 times than that of OTFT based on the untreated Al2O3 insulator, and the threshold voltage is reduced to -7 V. Meanwhile, the flat-band shift of the C-V characteristic of the MIS structure of Al2O3 after heat treatment is reduced, the result reveals that the annealing of Al2O3 insulator under HE atmosphere can reduce the trap density of the contact of Al2O3 insulator and pentacene, which leading to the performance improvement of OTFT with Al2O3 gate insulator treated under HE atmosphere.