一、双元素靶的制备 图1所示为背射Kossel线的衍射几何.聚焦的电子束通过靶管轰击到很薄的靶膜上,产生一个尺度很小的X射线点光源S,直径10—30μm. 由S发出充分发散的x射线入射到晶体上某一个衍射面时,总有一个入射圆锥满足Bragg条件,产生衍射.衍射线也形成一个圆锥,S’为衍射 I. Preparation of Dual-Element Target The diffraction geometry of the Kossel line in the back-illuminated area is shown in Figure 1. The focused electron beam impinges on the very thin target through the target tube, resulting in a very small X-ray point source S of diameter 10 -30μm. When the fully divergent x-rays emitted by S are incident on one of the diffraction planes of the crystal, there is always one incident cone that satisfies the Bragg condition, resulting in diffraction. The diffraction line also forms a cone and S ’is the diffraction