Abstract: A sandwich panel includes a first plate member and a second plate member, each of which is metallic, a spacer unit which is metallic and formed in the shape of a rectangular frame, and a core member. The core member is arranged in a region surrounded with the spacer unit between the first plate member and the second plate member. The spacer unit is made up of a plurality of spacers that are formed as separate members. The first plate member and the second plate member are bonded to the core member and each of the plurality of spacers.

Abstract: A sandwich panel includes a first plate member and a second plate member, each of which is metallic, a spacer unit which is metallic and formed in the shape of a rectangular frame, and a core member. The core member is arranged in a region surrounded with the spacer unit between the first plate member and the second plate member. The spacer unit is made up of a plurality of spacers that are formed as separate members. The first plate member and the second plate member are bonded to the core member and each of the plurality of spacers.

Abstract: A sandwich panel includes a first plate member and a second plate member, each of which is metallic, a spacer unit which is metallic and formed in the shape of a rectangular frame, and a core member. The core member is arranged in a region surrounded with the spacer unit between the first plate member and the second plate member. The spacer unit is made up of a plurality of spacers that are formed as separate members. The first plate member and the second plate member are bonded to the core member and each of the plurality of spacers.

Abstract: The surface of an epitaxial wafer is inspected using an optical scattering method. The intensities of light scattered with a narrow scattering angle and light scattered with a wide scattering angle reflected from laser light scatterers (LLS) on the wafer surface are detected. If the intensifies of narrowly and widely scattered lights are within a prescribed sizing range, it is judged whether the laser light scatterer is a particle or killer defect by deciding into which zone (410, 414, 418, 439) within the sizing range the PLS size based on the narrowly scattered light intensity and the PLS size based, on the widely scattered light intensity fall. If the intensity of the narrowly or widely scattered light exceeds the sizing range (417, 420, 421, 423, 424, 425), or if a plenty of laser light scatterers are continuous or concentrated (422), the laser light scatterers are judged to be killer defects.

Abstract: The surface of an epitaxial wafer is inspected using an optical scattering method. The intensities of light scattered with a narrow scattering angle and light scattered with, a wide scattering angle reflected from laser light scatterers (LLS) on the wafer surface are detected. If the intensifies of narrowly and widely scattered lights are within a prescribed sizing range, it is judged whether the laser light scatterer is a particle or killer defect by deciding into which zone (410, 414, 418, 439) within the sizing range the PLS size based on the narrowly scattered light intensity and the PLS size based, on the widely scattered light intensity fall. If the intensity of the narrowly or widely scattered light exceeds the sizing range (417, 420, 421, 423, 424, 425), or if a plenty of laser light scatterers are continuous or concentrated (422), the laser light scatterers are judged to be killer defects.