中文摘要：

利用超高真空扫描隧道显微镜对经过溴甲醇溶液腐蚀处理的液相外延碲镉汞材料进行了表征.发现经过腐蚀处理（3%浓度,2.5 min）的样品表面出现高密度的凹坑结构,凹坑深度约几十纳米,横向尺度在几十到几百纳米之间.扫描隧道谱测量表明,腐蚀样品表面平坦区呈现较大表观带隙,需考虑针尖诱导的能带弯曲效应,而凹坑区在零偏压区的扫描隧道谱线则近似为线性变化,说明该区域包含较高的带隙态并直接参与隧穿,从而掩盖了带隙信息.

英文摘要：

Ultra-high vacuum scanning tunneling microscopy （STM） and spectroscopy （ STS ） were used to characterize Hg1-xCdxTe grown by liquid-phase epitaxy （LPE） method. The sample was etched with 3% Bromine-methanol in 2.5 minutes. The STM images display submicrometer-sized pit structures with depths ranging from a few tens to a few hundreds nanometers. The scanning tunneling spectra show a larger apparent gap than the energy band gap of the btilk material due to the tip-induced band bending effect. In contrast, the scanning tunneling spectra of the pits show a finite slope through zero volt, implying the contribution of high density of band gap states which blur out the band gap information.