基于铁电极化调控的二维过渡金属硫属化物光电探测器

High performance micro/nanoscale optoelectronic devices are required urgently with the development of information technology. The two-dimensional (2D) semiconductor is one of the current research hotspots. It is meaningful and important for the development of new electronic / optoelectronic devices. This proposal is based on the 2D transition metal dichalcogenides (TMDs) and polyvinylidene fluoride (PVDF) based ferroelectric polymer. The 2D TMDs ferroelectric field effect transistor structure will be fabricated. The photo detector based on this structure will be studied. The carrier transport properties and band structure tunable properties of TMDs based on this structure under different ferroelectric polarization states will also be analyzed. Then, intrinsic mechanism of the photoelectric processing of the device with ferroelectric polarization gating will be verified. The next step, we will select the most appropriate material system, optimize the operation processing for the device structure. We will achieve the high performance photodetector based on TMDs with ferroelectric polarization manipulating. During the project, we can understand the intrinsic mechanism of the process of 2D semiconductor photoelectric detecting deeply, reveal rules of the new phenomena arising from the coupling of ferroelectric polarization and TMDs band structure. In addition, a theoretical, fundamental and technical guidance for designing new conception photodetector also be provided.

微纳尺度高性能光电器件是未来信息技术发展的必然要求，近年来兴起的二维半导体研究，为新型电子/光电子器件的研制注入了活力。本项目提出以二维过渡金属硫属化物半导体及聚偏氟乙烯（PVDF）基铁电聚合物材料为基础，构建基于铁电场效应管结构的二维过渡金属硫属化物光电探测器。通过研究铁电极化对不同二维过渡金属硫属化物载流子输运特性，能带结构调控规律；分析铁电极化对器件实现光电探测的内在物理机制；进而选择合适材料体系，优化材料制备工艺及器件结构设计、研制基于铁电极化调控的高性能二维半导体光电探测器件。通过该项目研究，一方面可深刻认识基于二维半导体光电探测过程的内在物理机理，揭示铁电极化与二维过渡金属硫化物能带结构耦合所产生诸如带隙调控等新物理现象或新效应的物理机制；另一方面为研制基于二维半导体材料的高性能新型红外探测器提供了新思路。

二维半导体在新型光电子器件的研发中具有潜力。然而，其吸收效率、稳定性、功耗等系列问题仍需要进一步解决。本项目研究了铁电材料与二维半导体相结合的晶体管器件，获得了此类场效应晶体管器件制备工艺；解析了极化电场-能带结构的内在关联，并研制出系列高性能光电子器件。铁电极化场可增强二维材料的光电性能，包括降低暗电流、提高灵敏度、拓展探测波长等，该方法具有普适性，亦适用于半导体纳米线器件。通过铁电材料周期性极化，调控双极性二维材料，实现了高性能PN结光伏型探测器；利用铁电畴调控，研制出双极性结型晶体管及电写入-光读出存储器等新型多功能器件。此外，通过热释电效应、极化特性以及二维材料光电导效应等多机制融合，实现了覆盖紫外至长波红外的超宽光谱响应探测器。综上，本研究揭示了极化场调控二维材料光电探测机理，为二维材料在高性能光电探测领域的应用提供了新的思路。