二维p-SnSe/n-SnSe2垂直异质结的可控合成及其高效光探测器的构筑

Two-dimensional (2D) p-n vertical heterostructure possesses many advantages such as tunable carrier concentration, low power consumption, and accessible integration due to the ultrathin thickness and large junction area, which shows promising applications in optoelectronics. Chemical vapor deposition (CVD) is an efficient method for synthesizing 2D materials. However, most reported 2D p-n vertical heterostructures via CVD are based on transition metal dichalcogenides (TMDs) with similar crystal structures, which may severely hamper the applications of 2D p-n vertical heterostructures in photodetectors. Thus it is urgent to explore novel 2D p-n vertical heterostructure. P-SnSe and n-SnSe2 are new members of 2D materials, and can compose a p-n heterostructure without hetero-atoms, which can avoid the degeneration of performance induced by the hetero-atom diffusion at junction. In this case, strategies of steady supplying for sources and multi-directional carrier gases are employed to realize the controllable synthesis of 2D p-SnSe/n-SnSe2 vertical heterostructure. Then, the correlation mechanism between the transportation of carriers and performance of photodetectors will be explored in order to improve the performance of photodetectors.

二维p-n垂直异质结超薄的厚度及较大的结区接触面积，使其具有载流子易调控、低能耗、高集成度等优势，在光探测器领域有极大的应用前景。CVD法是实现二维材料可控制备的有效手段，然而目前CVD法制备二维p-n垂直异质结的研究工作主要基于具有严格晶格匹配的过渡金属硫属化合物，严重限制了二维p-n垂直异质结在光探测器领域的应用。P-SnSe和n-SnSe2是由同种金属原子（Sn）和硫属原子（Se）组成的二维材料，将其用于构筑本征p-n异质结，可以有效避免结区异质原子扩散而引起的性能降低。因此，本项目旨在拟用近稳态供源技术与多向气路协同控制相结合的方式实现p-SnSe/n-SnSe2的垂直异质结的可控构筑，揭示其光探测器的载流子输运、复合等过程与器件性能的关联关系，实现高性能的p-SnSe/n-SnSe2垂直异质结光探测器的构筑。

二维p-n垂直异质结由于其超薄的厚度、较大的结区接触面积而具有载流子易调控、低能耗、高集成度等优势，赋予其在光探测器领域极大的应用前景。CVD法是实现二维材料可控制备的有效手段，然而目前CVD法制备二维p-n垂直异质结的研究工作主要集中于具有严格晶格匹配的过渡金属硫属化合物，严重限制了二维p-n垂直异质结在光探测器领域的应用。P-SnSe和n-SnSe2是由同种金属原子（Sn）和硫属原子（Se）组成的二维材料，将其用于构筑本征p-n异质结，可以有效避免结区异质原子扩散而引起的性能降低。本项目通过化学气相沉积方法实现p-SnSe/n-SnSe2的垂直异质结的可控构筑，并实现高性能的p-SnSe/n-SnSe2垂直异质结光探测器的构筑。项目执行期间，累计在Matter, Adv. Funct. Mater., Chem. Soc. Rev.等期刊上发表论文20篇，授权专利2项，指导（共同指导）毕业博士生3名，毕业硕士研究生5名。项目负责人入选第六届中国科协“青年人才托举工程”、湖北省“楚天学者计划”楚天学子、校学术新人奖等。通过本项目的实施，为未来二维材料器件的研究与应用奠定了基础。