Synchrotron Radiation Imaging Observation with Extremely Small Exit Angle for Lattice Mismatched Semiconductor Epitaxial

我们研制的X射线散射形貌术系统，能够利用同步辐射观测亚微米级横向空间分辨率的半导体外延层。我们提出的具有亚微米横向空间分辨率的散射形貌系统是直线型微针孔装置的主要组成部分。我们对Si、Ge、GaAs等大块样品中的位错进行了观察，获得了其他表征方法所没有得到的有价值的信息。对于外延膜，我们从未达到过比块状外延膜更好的观察效果。我们将尝试通过控制X射线穿透深度来表征在临界角附近的X射线衍射光学几何形状。通过光学测量测量了不同表面纳米形貌图案的硅片样品，并用掠入射衍射法和全反射成像法在临界角An…附近对不同表面形貌的硅片进行了表征更多的是使用平面波。我们使用了位于Spring8的BL20B2的中长(200m)弯曲磁束线上的高分辨率衍射地形站产生的平面波。GID形貌和全反射图像提供了表面粗糙度与硼掺杂浓度的关系的定性和详细的信息。此外，掠入射X射线衍射是基于一种称为面内衍射测量的新技术。等离子体辅助分子束外延生长的GaN外延层。利用面内衍射测量，我们可以获得关于GaN生长机制的重要信息。六方(纤锌矿)相通常与立方(闪锌矿)相共存，形成两种晶型(纤锌矿和锌混合结构)。平面2θ_χ/φ扫描GaN外延层的入射角关系：(A)闪锌矿GaN，(B)纤锌矿GaN，Cukα_1的临界角为0.206°。闪锌矿GaN的晶格间距与深度有关，而纤锌矿晶体的晶格间距与深度无关。较少

We develop X-ray scattering topography system, which is capable for observing a semiconductor epitaxial layer with sub-micron laterally spatial resolution using synchrotron radiation. The scattering topography system proposed by us with sub-micron laterally spatial resolution have a main component of a straight micro pinhole device. We have demonstrated observation for dislocations in Si, Ge, GaAs etc. bulk samples, and obtained valuable information which has never gotten by other characterization method. We had never reached better observation for epitaxial film than bulk one. We are going to try characterization of X-ray diffraction optical geometry at around critical angle with controlling of X-ray penetration depth.Silicon wafer specimens with different surface nanotopography patterns, as measured by optical measurements, and different boron concentrations, were characterized by a grazing incident diffraction (GID) topography and total reflection imaging method near the critical an … More gle using plane-waves. We used plane-waves produced by the high-resolution diffraction topography station located at the medium-length (200 m) bending-magnet beam line at BL20B2 of SPring-8. The GID topographs and total reflection images gave qualitative and detailed information on the dependence of surface roughness on boron doping concentration. Moreover, grazing incident X-ray diffraction is based on the new technique called in-plane diffraction measurement. GaN epitaxial layer grown by plasma-assisted molecular beam epitaxy on GaAs (001) substrate. Using the in-plane diffraction measurement, we could obtain significant information concerning to GaN growth mechanism. The hexagonal (wurtzite) phase often co-exists with cubic (zinc blende) one for two-polymorphs (wurtzite and zinc-blend structures). Incident angle dependence of GaN epitaxial layer for in plane 2θ_χ/φ-scannning diffraction intensity (a) zincblende-GaN, (b) wurtzite-GaN, critical angle ω_c is 0.206° for CuKα_1. While the lattice spacing for GaN_<zinc blende> || have a dependence of depth, that for GaN_<wurtzite> crystal have no depth dependence. Less