晶体位错处理对X射线衍射性能的影响

为提高晶体对波长为0.1~20 nm的X射线的衍射效率，通过特殊工艺对特定晶体表面进行位错处理。将云母、α-石英和LiF晶体劈成80 mm×10 mm的晶体薄片，其中LiF晶体厚度研磨到1 mm，其余三种晶体厚度为0.2 mm。将LiF晶体加热到400 ℃，然后用椭圆型折弯机进行多次弯曲，自然冷却降到室温，使晶格发生位错现象。在波长为0.154 nm的Cu靶X射线衍射仪上进行衍射试验，经晶体后利用成像板或X射线CCD获得衍射谱线，其中Mica球弯晶获得多级衍射谱线，经过表面处理的LiF晶体获取的X射线光子数比未处理的高2倍。结果表明晶体表面经过位错处理后提高了衍射效率，更适合X射线诊断研究。

Influence on X-ray Diffraction by Crystal′s Surface Dislocation Treatment

To improve the crystal X-ray diffraction efficiency in wavelength range of 0.1~20 nm, it is processed that crystal surface is dealt with specific technique. Those crystals, such as mica、α-quartz and LiF, are cleaved slice of 80 mm×10 mm, with LiF crystal thickness of 1 mm, other crystals thickness of 0.2 mm. LiF crystal is heated up to about 400 ℃, then bended by curved-machine time after time and cooled to room temperature by natural, resulting in a so-called dislocation phenomenon which leads to enhance diffractive efficiency. The experience is carried on a Cu target X-ray diffractometer (XRD) with wavelength of 0.154 nm. Muti-diffractive phenomenon happens on mica spherical surface crystal. Double intensity is achieved on processed LiF crystal surface compared to original crystal. The experimental results show that it is more suitable to diagnose soft X-ray after treating the crystal surface for improving dislocation.