标题： 2H-TaS$_2$少层在GaN(0001)上的分子束外延 显示英文标题

标题： Molecular Beam Epitaxy of 2H-TaS$_2$ few-layers on GaN(0001)

摘要： 2H-TaS$_2$的几层在GaN(0001)上外延生长。 高温的衬底生长温度825$^{\circ}$摄氏度使覆盖层具有最佳的结构特性，这由原位电子衍射（RHEED和LEED）揭示。 二维覆盖层在单层沉积后立即无应变生长。 然而，扫描透射电子显微镜提供了界面处凹坑的证据，最可能是由于在高温生长条件下GaN的热分解所致。 原位X射线光电子能谱显示核心能级偏移与从n-GaN(0001)到2H-TaS$_2$外延层的电子转移以及界面附近氮空位高浓度的形成一致。 此外，从XPS推断出衬底和生长的TaS$_2$覆盖层之间没有化学反应，这证实了将二维2H-TaS$_2$与像GaN这样的重要三维半导体材料集成的可能性。 显示英文摘要

摘要： 2H-TaS$_2$ few layers have been grown epitaxially onto GaN(0001). A high substrate growth temperature of 825$^{\circ}$C induces best structural properties of the overlayer, as revealed by in-situ electron diffraction (RHEED and LEED). The 2D-overlayer grows unstrained right after deposition of a monolayer. However, evidence of pits at the interface is provided by scanning transmission electron microscopy, most probably due to GaN thermal decomposition at the high growth temperature. In-situ x-ray photoemission spectroscopy shows core level shifts that are consistently related to electron transfer from the n-GaN(0001) to the 2H-TaS$_2$ epitaxial layer as well as the formation of a high concentration of nitrogen vacancies close to the interface. Further, no chemical reaction at the interface between the substrate and the grown TaS$_2$ overlayer is deduced from XPS, which corroborates the possibility of integration of 2D 2H-TaS$_2$ with an important 3D semiconducting material like GaN.