论文标题
通过瞬态电容测量和原子分辨率化学分析探测的SIO2/4H-SIC接口处的电子捕获
Electron trapping at SiO2/4H-SiC interface probed by transient capacitance measurements and atomic resolution chemical analysis
论文作者
论文摘要
研究与碳化硅（4H-SIC）的栅极氧化物（SIO2）界面的电和结构特性是一个基本主题，对理解和优化金属氧化物 - 氧化物 - 氧化物 - 氧化物 - 导向器场效应晶体管（MOSFET）的性能具有重要意义。在本文中，研究了4H-SIC MOSFET中近界面氧化物陷阱（NIOTS（NIOTS），研究了瞬态栅极电容测量值（C-T）和电子能量损耗光谱（STEM-EELS）中的ART扫描透射电子显微镜的状态与亚NM分辨率。 C-T测量值随温度的函数表明，有效的NIOTS放电时间与温度无关，并且通过调节将NIOT的电子发射到半导体上。同时考虑了隧道弛豫模型中的界面状态密度，对NIOTS的排放时间进行了建模，并允许在距SIO2/4H-SIC接口最高1.3nm的隧道距离内定位陷阱。另一方面，子-NM分辨率干eels揭示了存在非破裂（NA）SIO2/4H-SIC界面的存在。 Na界面显示了亚化学计量学SIOX矩阵中碳原子的重新排列。 Na界面区域中混合的SP2/SP3碳杂交表明，界面碳原子已经失去了四面体SIC协调。
Studying the electrical and structural properties of the interface of the gate oxide (SiO2) with silicon carbide (4H-SiC) is a fundamental topic, with important implications for understanding and optimizing the performances of metal-oxide-semiconductor field effect transistor (MOSFETs). In this paper, near interface oxide traps (NIOTs) in lateral 4H-SiC MOSFETs were investigated combining transient gate capacitance measurements (C-t) and state of the art scanning transmission electron microscopy in electron energy loss spectroscopy (STEM-EELS) with sub-nm resolution. The C-t measurements as a function of temperature indicated that the effective NIOTs discharge time is temperature independent and electrons from NIOTs are emitted toward the semiconductor via-tunnelling. The NIOTs discharge time was modelled taking into account also the interface state density in a tunnelling relaxation model and it allowed to locate traps within a tunnelling distance up to 1.3nm from the SiO2/4H-SiC interface. On the other hand, sub-nm resolution STEM-EELS revealed the presence of a Non-Abrupt (NA) SiO2/4H-SiC interface. The NA interface shows the re-arrangement of the carbon atoms in a sub-stoichiometric SiOx matrix. A mixed sp2/sp3 carbon hybridization in the NA interface region suggests that the interfacial carbon atoms have lost their tetrahedral SiC coordination.
