Department of Physics and Centre for Plastic Electronics, Blackett Laboratory, Imperial College London, London SW7 2BW, UK.
Phys Chem Chem Phys. 2011 Aug 28;13(32):14387-93. doi: 10.1039/c1cp20769e. Epub 2011 Jun 20.
The electrical stability of low-voltage organic transistors based on phosphonic acid self-assembled monolayer (SAM) dielectrics is investigated using four different semiconductors. The threshold voltage shift in these devices shows a stretched-exponential time dependence under continuous gate bias with a relaxation time in the range of 10(3)-10(5) s, at room temperature. Differences in the bias instability of transistors based on different self-assembled monolayers and organic semiconductors suggest that charge trapping into localized states in the semiconductor is not the only mechanism responsible for the observed instability. By applying 1-5 s long programming voltage pulses of 2-3 V in amplitude, a large reversible threshold voltage shift can be produced. The retention time of the programmed state was measured to be on the order of 30 h. The combination of low voltage operation and relatively long retention times makes these devices interesting for ultra-low power memory applications.
基于膦酸自组装单分子层（SAM）电介质的低压有机晶体管的电稳定性，使用四种不同的半导体进行了研究。在室温下，这些器件的栅极偏置下的阈值电压漂移显示出连续偏置下的拉伸指数时间依赖性，弛豫时间在 10(3)-10(5) s 范围内。基于不同自组装单层和有机半导体的晶体管的偏置不稳定性的差异表明，电荷捕获到半导体中的局部态不是导致观察到的不稳定性的唯一机制。通过施加幅度为 2-3 V 的 1-5 s 长编程电压脉冲，可以产生大的可逆阈值电压漂移。编程状态的保持时间测量约为 30 h。低电压操作和相对较长的保持时间的组合使得这些器件在超低功率存储应用中很有趣。
