Department of Electronic Engineering and Materials Science and Technology Research Centre, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
ACS Appl Mater Interfaces. 2011 Dec;3(12):4662-7. doi: 10.1021/am201078v. Epub 2011 Nov 9.
In this study, low-voltage copper phthalocyanine (CuPc)-based organic field-effect transistors (OFETs) are demonstrated utilizing solution-processed bilayer high-k metal-oxide (Al(2)O(y)/TiO(x)) as gate dielectric. The high-k metal-oxide bilayer is fabricated at low temperatures (< 200 °C) by a simple spin-coating technology and can be controlled as thin as 45 nm. The bilayer system exhibits a low leakage current density of less than 10(-5) A/cm(2) under bias voltage of 2 V, a very smooth surface with RMS of about 0.22 nm and an equivalent k value of 13.3. The obtained low-voltage CuPc based OFETs show high electric performance with high hole mobility of 0.06 cm(2)/(V s), threshold voltage of -0.5 V, on/off ration of 2 × 10(3) and a very small subthreshold slope of 160 mV/dec when operated at -1.5 V. Our study demonstrates a simple and robust approach that could be used to achieve low-voltage operation with solution-processed technique.
在这项研究中，利用溶液处理的双层高介电常数金属氧化物（Al 2 O(y)/TiO(x)）作为栅介质，展示了低压铜酞菁（CuPc）基有机场效应晶体管（OFET）。高介电常数金属氧化物双层通过简单的旋涂技术在低温（<200°C）下制备，厚度可低至 45nm。该双层系统在 2V 偏压下的漏电流密度小于 10(-5)A/cm(2)，表面非常光滑，均方根值约为 0.22nm，等效 k 值为 13.3。所获得的基于低压 CuPc 的 OFET 表现出优异的电性能，空穴迁移率高达 0.06cm(2)/(V s)，阈值电压为-0.5V，开关比为 2×10(3)，在-1.5V 下工作时亚阈值斜率非常小，为 160mV/dec。我们的研究展示了一种简单而稳健的方法，可以通过溶液处理技术实现低压操作。
