Patent Number: 
Section: claims

1. An X-ray topography apparatus that uses X-rays for form two-dimensional images in correspondence with an internal structure of a sample, comprising:an X-ray source that produces X-rays with which the sample is irradiated;a multilayer film mirror provided in a position between the sample and the X-ray source;a slit member provided in a position between the sample and the X-ray source and including a slit that limits a width of the X-rays;two-dimensional X-ray detection means for two-dimensionally detecting X-rays having exited out of the sample; andsample moving means for achieving stepwise movement of the sample relative to the X-rays with which the sample is irradiated to sequentially move the sample to a plurality of step positions, wherein:the X-ray source produces the X-rays from a minute focal spot,the multilayer film mirror converts the X-rays emitted from the X-ray source into monochromatic, collimated, high-intensity X-rays,the direction in which the multilayer film mirror collimates the X-rays coincides with a width direction of the slit of the slit member,the step size by which the sample moving means moves the sample is smaller than a width of the slit, andthe combination of the size of the minute focal spot, the width of the slit, and the intensity of the X-rays that exit out of the multilayer film mirror allows the contrast of an X-ray image produced when the two-dimensional X-ray detection means receives the X-rays for a predetermined period of 1 minute or shorter to be high enough for observation of the X-ray image. 2. The X-ray topography apparatus according to claim 1, further comprising a processor, wherein the processor is configured to:acquire a two-dimensional cross-sectional image associated with each of the plurality of step positions, wherein the two-dimensional cross-sectional image is produced by irradiating the sample with the X-rays in each of the plurality of step positions for the predetermined period and detecting X-rays having exited out of the sample irradiated with the X-rays with the two-dimensional X-ray detection means, thereby acquiring a plurality of two-dimensional cross-sectional images,form a three-dimensional image by arranging the plurality of two-dimensional cross-sectional images, andacquire a second two-dimensional image by extracting data along a flat plane different from measurement planes associated with the three-dimensional image. 3. The X-ray topography apparatus according to claim 2, wherein the processor is further configured to calculate dislocation density based on the second two-dimensional image. 4. The X-ray topography apparatus according to claim 3, wherein the minute focal spot comprises a focal spot so sized as to fall within a circle having a diameter of 100 μm, and the width of the slit ranges from 10 to 50 μm. 5. The X-ray topography apparatus according to claim 4, wherein the multilayer film mirror comprises a parabolic form, so as to allow X-rays incident on the sample to be diffracted in parallel to each other. 6. The X-ray topography apparatus according to claim 5, wherein interplanar spacing of lattice planes in the multilayer film mirror is so differentiated from each other location-to-location that the X-rays incident at different angles of incidence are reflected off the entire surface of the multilayer film mirror.