同质硅分子束外延层的界面缺陷的研究

A STUDY OF THE INTERFACIAL DEFECTS IN MOLECU- LAR BEAM EPITAXIAL SILICON

对同质硅分子束外延层的界面缺陷进行了测试与分析．对存在高浓度施主型界面缺陷的Ｐ型材料，通过解泊松方程计算了该材料的肖特基势垒的能带图，得到了该缺陷能级上电子的填充与发射随外加反向偏压变化的情况．并分析了用深能级瞬态谱（ＤＬＴＳ）对其进行测试所需的条件，以及与常规的ＤＬＴＳ测试结果的不同之处．提出了可同时对该缺陷上电子的发射和俘获过程进行ＤＬＴＳ测量的方法．实验测量结果表明，该高密度的界面缺陷的能级位置位于Ｅ＿ｃ－０．３０ｅＶ．

The interfacial defects at the p-Si MBE layer/P-Si substrate interface have beenobserved and analysed.By solving Poisson equation,we can obtain the energy banddiagram for this kind of structure with Shottky barrier at the surface and high den- sity defects at the interface.The electron concentration at the defect level varyingwith external voltage can also be got by the calculation. Using deep level transientspectrascopy(DLTS)measurement to detect the interfacial defects,we found thatthe DLTS spectra for the emission and capture of electrons by the defect level canbe got simultaneously at one temperature scan and the difference from conventionalDLTS method is also discussed.The experimental results show that the energylevel of the interface defects is located at E_c-0.30eV.