In an x-ray absorber in accordance with the present invention, reduced transmittance
of the x-ray absorber is suppressed while phase shift amount in the vicinity of
-radians is achieved. For this purpose, a material is used that has a high
transmittance per film thickness and contains an element with a high phase shift
amount and an element with a low transmittance, as a material composition that
forms the x-ray absorber. In other words, the transmittance of the x-ray absorber
is mainly determined by the element with a low transmittance, and phase shift falling
short of -radians is compensated with the element with a high transmittance
and a high phase shift.
