Analysis of Multilayer Structure Constituted by Light-Elements with Total Reflection PIXE

建立了全反射PIXE谱线。制备了两个多层样品。一种是在光学平板上制备的CaF_2（1 nm）/LiF（33 nm）/Cu（100 nm）。另一种是将蛋白质单层膜置于镀有Cr的平板玻璃上，用1 MeV质子束在全反射条件（TPIXE）和垂直条件（PIXE）下轰击Ca样品。观察到了特征的X射线干涉条纹。这些条纹是在来自Ca的X射线的直接发射和由衬底表面全反射的发射之间产生的，并且通过用Si（Li）检测器扫描狭缝来测量。用TPIXE和PIXE对样品进行了三次干涉条纹的测量，在TPIXE中观察到了几乎相同的条纹，在PIXE中，在第2和第3段没有观察到，说明Ca样品是被垂直方向的质子束轰击破坏的。在10 ℃和-30 ℃条件下，用TPIXE对蛋白质单层膜中的S射线进行了分析，从出发角数据分析可知，在-30 ℃条件下，质子束对蛋白质单层膜没有破坏，TPIXE可用于蛋白质单层膜中微量元素的定位。

The total reflection PIXE (TPIXE) line was constructed. Two multilayer samples were prepared. One was CaF_2 (lnm)/LiF (33nm)/Cu (l00nm) which was prepared on an optical flat quartz plate. The other was protein monolayer film which was placed on the flat glass plate coated with Cr.The Ca sample was bombarded with 1MeV proton beam in the total reflection conditions (TPIXE) and vertically conditions (PIXE). The characteristic x-ray interference fringes were observed. These fringes are generated between the direct emissions of x-ray from Ca and the emissions totally reflected by the substrate surface, and are measured by scanning the slit with a Si (Li) detector. The measurement of the interference fringes were carried out three times by TPIXE and PIXE.Almost same fringes were observed in TPIXE.These fringes was observed at first measurement, but could not be observed at second and third in PIXE.It is concluded that Ca sample was destroyed by the bombardment of the proton beam in vertically.The measurements of the take-off angle dependent of the characteristic x-ray from S in the protein monolayer film were carried out with TPIXE at 10ﾟC and -30ﾟC.From the analysis of the data of the take-off angle, the protein film was not destroyed by proton beam at -30ﾟC, but it was gradually destroyed at 10ﾟC.It was concluded that TPIXE could be applied to determine the site of the lite-element in the protein monolayer film.