Si-Si直接键合的杂质分布

Impurity Distribution of Silicon Direct Bonding

在Si-Si直接键合过程中,界面处存在一层很薄的厚度恒定的本征SiO2.Si对SiO2中的杂质的抽取效应,导致了杂质在界面处的浓度大大降低,根据改进了的杂质在Si-Si直接键合片中分布模型,推导出了杂质分布的表达式,在理论上和实验上都对该式进行了验证.杂质通过SiO2再向Si中扩散的杂质总量与Si-Si扩散相比大大减少,使所形成的p-n+结的结深减小.

There is a thin layer of native oxide between two directly bonded silicon wafers. The silicon extracts impurity from the oxide,thus drastically decreasing the impurity concentration at the interface of SiOz-Si. Based on the modified model of silicon direct bonding, an expression of impurity distribution is derived and verified by theory and experiment. Finally, it is found that the total impurity in silicon with oxide is much less than that without oxide ,which decreases the junction depth of p^- n^＋ junction.