二维单质磷光电探测器:基于范德华电极接触的器件机理研究

Two-dimensional single-substance phosphor photodetectors:A device mechanism study based on van der Waals electrode contacts

以黑磷为代表的单质磷已成为先进半导体器件探索的关键参与者,适用于中红外波段各种光子和光电设备.作为同素异形体的紫磷呈宽带隙特征,具有更复杂的晶格结构,在可见光波段有应用前景.但由于紫磷与金属间较大的肖特基势垒,阻碍了其器件性能表现.最新的研究借助范德华作用,用二维材料与紫磷做电极接触,屏蔽了费米钉扎效应的影响,实现了器件高性能表现.进一步地与黑磷组成垂直型同素异形体异质结,实现了更高的响应速度,并澄清了其一类异质结能带特性.

Represented by black phosphorus,elemental phosphorus has become a key participant in the exploration of advanced semiconductor devices,suitable for various photonics and optoelectronic devices in the mid-infrared range.As an allotrope,violet phosphorus exhibits wide bandgap characteristics and has potential applications in the visible light spectrum due to its more complex lattice structure.However,its device performance has been hindered by the large Schottky barrier between violet phosphorus and metals.In recent research,van der Waals interactions have been utilized to create electrical contacts between two-dimensional materials and violet phosphorus,effectively shielding the Fermi level pinning effect and achieving high-performance device behavior.Furthermore,combining violet phosphorus with black phosphorus in a vertical heterostructure has led to even higher response speeds,and clarified that it belongs to the first type of heterojunction energy band characteristics.