CAJ | 학술논문

碳化硅（ SiC）作为一种新型材料被广泛应用于高功率半导体器件中。目前的SiC基金属氧化物半导体场效应晶体管器件存在的主要问题是沟道电子迁移率低。 SiC／SiO2界面处的过渡层被认为是造成沟道电子迁移率低的主要原因，但是该过渡层的原子结构尚不清楚。本文利用球差矫正扫描透射电子显微镜深入研究了SiC／SiO2的界面。以变聚焦序列技术得到了界面过渡层不同深度的原子分辨率断层扫描图像，用变聚焦序列图像重构了界面的原子分辨率三维结构。精确的界面原子结构表明SiC／SiO2界面处的过渡区是由于邻晶界面上台阶突起和微刻面构成的。它是界面原子尺度的粗糙度的反映。邻晶界面上的台阶突起和微刻面增加了电子在界面传输过程中的散射几率，造成了沟道电子迁移率过低。
탄화규（ SiC）작위일충신형재료피엄범응용우고공솔반도체기건중。목전적SiC기금속양화물반도체장효응정체관기건존재적주요문제시구도전자천이솔저。 SiC／SiO2계면처적과도층피인위시조성구도전자천이솔저적주요원인，단시해과도층적원자결구상불청초。본문이용구차교정소묘투사전자현미경심입연구료SiC／SiO2적계면。이변취초서렬기술득도료계면과도층불동심도적원자분변솔단층소묘도상，용변취초서렬도상중구료계면적원자분변솔삼유결구。정학적계면원자결구표명SiC／SiO2계면처적과도구시유우린정계면상태계돌기화미각면구성적。타시계면원자척도적조조도적반영。린정계면상적태계돌기화미각면증가료전자재계면전수과정중적산사궤솔，조성료구도전자천이솔과저。
Silicon carbide ( SiC) is widely used in high power electronics as a substitute of silicon. The key problem of SiC based metal?oxide?semiconductor field effect transistors ( MOSFET) is the relatively low channel electron mobility, and the transition layer of SiC/SiO2 interface is considered to be the main cause for the reduced electron mobility. However, the atomic structure of the transition layer is still unclear. In this paper, the transition layer was investigated with a 5th order spherical aberration corrected scanning transmission electron microscope. Depth sectioning images of SiC/SiO2 interface were obtained with the through?focal series technique, and an atomic resolution 3D structure of the interface was reconstructed with the through?focal series images. The clear 3D interface structure suggests that tshe interface has an atomic scale roughness, and the transition layer is a contrast of the roughness. The kinks, steps and microfacets increase the scattering probability of channel electrons, resulting in reducing the channel mobility of the MOSFET devices.