Abstract

The electronic structure of the epitaxial GaN/Si(111) layers and the Li/GaN/Si(111) interface with a monolayer Li coverage has been studied in situ under ultrahigh vacuum conditions. The experiments were carried out using photo electron spectroscopy with synchrotron radiation in the photon energy range 75–850 eV. The photoemission spectra in the valence band and the core levels of Ga 3d, N 1s, and Li 1s are studied for the monolayer Li coating. It is found that Li adsorption causes a significant decrease in the intensity of the photoemission line of the intrinsic surface state and the appearance of an induced surface state due to charge transfer between the adsorbed Li layer and surface Ga atoms. It has been found that the GaN/Si(111) surface has predominantly Ga polarity. The Li/GaN/Si(111) interface has a semiconductor character.

中文翻译：

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Li吸附下GaN/Si(111)表面电子性质的变化

摘要

在超高真空条件下原位研究了外延 GaN/Si(111) 层和单层 Li 覆盖的 Li/GaN/Si(111) 界面的电子结构。实验使用光子能量范围 75-850 eV 的同步加速器辐射光电子能谱进行。研究了单层Li涂层的Ga 3 d、N 1 s和Li 1 s的价带和核心能级的光电发射光谱。研究发现，Li的吸附导致本征表面态的光发射线强度显着降低，并且由于吸附的Li层和表面Ga原子之间的电荷转移而出现诱导表面态。已经发现GaN/Si(111)表面主要具有Ga极性。Li/GaN/Si(111)界面具有半导体特性。