Chen Zetian, Sheleg Gil, Shekhar Himanshu, Tessler Nir
The Zisapel Nano-Electronics Center, Department of Electrical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
ACS Appl Mater Interfaces. 2020 Apr 1;12(13):15430-15438. doi: 10.1021/acsami.9b22165. Epub 2020 Mar 17.
We report an optoelectronic device consisting of a solution-processed indium gallium zinc oxide (IGZO) thin-film transistor and vacuum-deposited small organic molecules. Depending on the configurations of the organic materials, either bulk heterojunction or planar heterojunction (PHJ), the device assumes the functionality of either a photosensor or a photoinduced memory, respectively. Under λ = 625 nm light illumination, the photosensor shows response and recovery time of ∼50 ms, responsivity of ∼5 mA/W, sensitivity above 10, and a linear response. The mechanism of the photoinduced memory is studied experimentally and verified using a device simulation. We find that the memory is due to long charge retention time at the organic PHJ interface which is stable for over 9 days. It is correlated with the low leakage current found in ordered organic junctions having low subgap tail states. The presented integration of the PHJ with the transistor constitutes a new design of write-once-read-many-times memory device that is likely to be attractive for low-cost applications.
我们报道了一种光电器件，它由溶液处理的铟镓锌氧化物（IGZO）薄膜晶体管和真空沉积的小有机分子组成。根据有机材料的配置，即体异质结或平面异质结（PHJ），该器件分别具有光电传感器或光致存储器的功能。在λ = 625 nm光照下，光电传感器的响应和恢复时间约为50 ms，响应度约为5 mA/W，灵敏度高于10，且具有线性响应。通过实验研究了光致存储器的机制，并使用器件模拟进行了验证。我们发现，该存储器是由于有机PHJ界面处的长电荷保留时间，其稳定性超过9天。这与在具有低带隙尾态的有序有机结中发现的低泄漏电流相关。所展示的PHJ与晶体管的集成构成了一种一次性写入多次读取存储器件的新设计，这可能对低成本应用具有吸引力。
