| 摘要 |
PURPOSE:To observe the state of a considerably shallow part immediately below the surface of a crystal by optimizing the wavelength of X-rays and setting the angle of incidence in the vicinity of a critical angle. CONSTITUTION:X-rays including a continuous spectrum are taken out from an X-ray source, and a monochromatic X-ray 16b of a specific wavelength among the spectral components is taken out by a double-crystal spectrometer. When the wavelength of the X-ray 16b cast to a surface 12 of a crystal 10 is set to be near 1.35Angstrom and an angle of incidence alphab is set in the vicinity of tone critical angle, the X-ray 16b can be totally reflected while the condition for diffraction (angle beta defined by the surface 12 and a surface of diffraction 11 is equal to 45 deg.) is satisfied. However not all the light is reflected at the surface 12, but there is a light wave advancing parallel to the surface 12 and suddenly attenuating the amplitude exponentially in proportion to the distance from the surface 12. Therefore, the diffraction phenomenon by the X-ray corresponding to this light wave is brought about at a considerably shallow part immediately below tone surface 12. It is accordingly possible to evaluate the state of the considerably shallow part immediately below the surface 12 when the intensity of a diffraction X-ray. |
