A wafer inspection apparatus including a light emitter configured to emit light onto a to-be-inspected surface of a wafer, an imaging unit configured to obtain an image formed by the light emitted from the light emitter and reflected by the to-be-inspected surface, a moving unit configured to move a to-be-inspected position on the to-be-inspected surface by controlling a position of one of the wafer and the light emitter, and an inspecting unit configured to inspect the to-be-inspected surface by detecting a scatter image formed by the light that is emitted from the light emitter and scattered by a defect of the to-be-inspected surface, where the scatter image is formed outside an outline of the image formed by the light emitted from the light emitter.

A nitride crystal is characterized in that, in connection with plane spacing of arbitrary specific parallel crystal lattice planes of the nitride crystal obtained from X-ray diffraction measurement performed with variation of X-ray penetration depth from a surface of the crystal while X-ray diffraction conditions of the specific parallel crystal lattice planes are satisfied, a uniform distortion at a surface layer of the crystal represented by a value of |d.sub.1d.sub.2|/d.sub.2 obtained from the plane spacing d.sub.1 at the X-ray penetration depth of 0.3 m and the plane spacing d.sub.2 at the X-ray penetration depth of 5 m is equal to or lower than 2.110.sup.3. The above configuration provides the nitride crystal having a crystal surface layer that is evaluated directly and reliably without breaking the crystal so that it can be used in a preferred fashion as a substrate for a semiconductor device as well as the nitride crystal substrate, an epilayer-containing nitride crystal substrate, a semiconductor device and a method of manufacturing the same.

A nitride crystal is characterized in that, in connection with plane spacing of arbitrary specific parallel crystal lattice planes of the nitride crystal obtained from X-ray diffraction measurement performed with variation of X-ray penetration depth from a surface of the crystal while X-ray diffraction conditions of the specific parallel crystal lattice planes are satisfied, a uniform distortion at a surface layer of the crystal represented by a value of |d.sub.1d.sub.2|/d.sub.2 obtained from the plane spacing d.sub.1 at the X-ray penetration depth of 0.3 m and the plane spacing d.sub.2 at the X-ray penetration depth of 5 m is equal to or lower than 2.110.sup.3. The above configuration provides the nitride crystal having a crystal surface layer that is evaluated directly and reliably without breaking the crystal so that it can be used in a preferred fashion as a substrate for a semiconductor device as well as the nitride crystal substrate, an epilayer-containing nitride crystal substrate, a semiconductor device and a method of manufacturing the same.

Integrated backscatter X-ray assemblies for detecting backscatter X-rays reflected by a target area of an article under test are disclosed. The integrated backscatter X-ray assembly includes an enclosure, an X-ray power supply, an X-ray tube, a backscatter X-ray detector and a cooling fluid. The X-ray power supply disposed within the enclosure. The X-ray tube disposed within the enclosure and operatively coupled to the X-ray power supply. The backscatter X-ray detector is disposed within the enclosure. The cooling fluid disposed within the enclosure such that the X-ray power supply, the X-ray tube and the backscatter X-ray detector are immersed in the cooling fluid. In various examples, integrated backscatter X-ray assemblies may also include a movable base and/or a mobile platform. Methods for detecting backscatter X-rays reflected by a target area of an article under test are also disclosed.

Provided is a method for estimating abrasion resistance of polymer composite materials. The present disclosure relates to a method for estimating abrasion resistance, the method including: irradiating a sulfur compound-containing polymer composite material with high intensity X-rays; measuring an X-ray absorption in a small region of the polymer composite material while varying an energy of the X-rays, whereby a dispersion state and a chemical state of the sulfur compound are analyzed; and quantifying an inhomogeneous state of cross-link degradation in the polymer composite material based on the dispersion state and the chemical state.

A method for determining a deformation field of at least one layer of paint applied to a support during crosslinking of the layer or the layers of paint is disclosed. The method includes a step (E1) of provision of a sample, a step (E2) of 3D tomographic measurement of the sample and a set of successive steps(S) repeated iteratively comprising a step (E3) of dynamic mechanical analysis of the sample subjected to at least one temperature cycle (C), a step (E4) of 3D tomographic measurement of the sample, a step (E5) of determining a deformation field of each layer of paint of the sample.