A New in-situ Optical Probing Method for the Surface Reaction in Heteroepitaxy : Surface Photo-Interference

提出了一种新的原位光学探测方法来研究异质外延生长过程中的表面反应。这种新方法被命名为表面光干涉（SPI），因为SPI的概念本质上是与异质层中的光干涉有关。该方法的实验设置与另一种称为表面光吸收（SPA）的光学探测方法非常相似，但两者的原理有很大不同。与SPA不同的是，相当低能量的光子对于epilayr来说是透明的，也可以在SPI中用作探测光。反映了这一特性，SPI对于研究宽间隙II-VI化合物异质外延生长的生长动力学特别有用，因为当使用这种低能光子作为探测光时，可以避免光催化生长速率增强的影响。给出了SPI信号的理论描述，并详细讨论了在ZnSe和CdSe的MOMBE中检测到的实验结果。此外，还讨论了SPI与SPA的区别。

A new in-situ optical probing method for studying surface reactions during heteroepitaxial growth has been proposed. The new method was named surface photo-interference (SPI) , because the concept of the SPI is essentially concerned with a photo-interference in the heteroepilayr. The experimental setup of the method is very similar to another optical probing method called surface photo-absorption (SPA) , but the principle is quite different between the two. Unlike SPA,fairly low energy photons that are transparent for the epilayr can also be used in SPI as a probing light. Reflecting this feature, SPI is especially useful for studying growth kinetics in heteroepitaxial growth of widegap II-VI compounds, because the effect of photocatalytic growth-rate enhancement can be avoided when using such low energy photons as a probing light. A theoretical description of SPI signal was given, and experimental results detected in MOMBE of ZnSe and CdSe were precisely discussed. Further, how SPI differs from SPA has also been discussed.