Abstract: A semiconductor device, including: a semiconductor chip formed on a heat dissipation plate; a pool part including a bottom surface, two long lateral faces, and two short lateral faces defining a pool space; a guide part installed in the pool space and having first and second ends both connected to one of the short lateral face, at positions opposite to each other across an inlet formed on the one short lateral face, so as to separate a guide space from the pool space; and a guide plate disposed in the pool space on the guide part. In the plan view, the guide plate has a slit formed within an area thereof overlapping the guide space. The heat dissipation plate is disposed on the pool part. A geometrical area of a cross-section of the guide space becomes smaller as the cross-section is farther away from the inlet of the pool part.

Abstract: A cooler includes first and second flow paths inside a container, respectively communicating with an inlet and an outlet, a third flow path, and first and second flow rate adjusting members respectively disposed between the first and third flow paths, and the second and third flow paths. The first flow rate adjusting member includes one or more openings through which a coolant flows from the first flow path to the third flow path, and has a first region with a first open area ratio and a second region with a second open area ratio less than the first one. The second flow rate adjusting member includes one or more openings through which the coolant flows from the third flow path to the second flow path, and has a third region with a third area ratio and a fourth region with a fourth open area ratio greater than the third one.

Abstract: Provide is an ultraviolet ray transmissive filter in which a crystal structure of a hafnium oxide layer is controlled to improve the light resistance of an optical interference film, and which can suppress reduction of the transmissivity in a transmission band even under long-term irradiation with ultraviolet rays. The optical interference film includes the hafnium oxide layer, and in the crystal structure of the hafnium oxide layer, spectral peak intensities from X-ray diffraction which are derived from the orthorhombic crystal structure and a tetragonal crystal structure are lower than a spectral peak intensity from X-ray diffraction which is derived from the monoclinic crystal structure.

Abstract: Provide is an ultraviolet ray transmissive filter in which a crystal structure of a hafnium oxide layer is controlled to improve the light resistance of an optical interference film, and which can suppress reduction of the transmissivity in a transmission band even under long-term irradiation with ultraviolet rays. The optical interference film includes the hafnium oxide layer, and in the crystal structure of the hafnium oxide layer, spectral peak intensities from X-ray diffraction which are derived from the orthorhombic crystal structure and a tetragonal crystal structure are lower than a spectral peak intensity from X-ray diffraction which is derived from the monoclinic crystal structure.