Power semiconductor module and power module using same

The purpose of the present invention is to provide: a power semiconductor module which has excellent thermal conductivity; and a power module which uses this power semiconductor module. In order to achieve the above-mentioned object, a power semiconductor module according to the present invention is characterized by comprising: a semiconductor element; a conductor plate, on one surface of which the semiconductor element is mounted; a resin sealing part which covers a lateral surface part of the conductor plate, while having at least a part of the other surface of the conductor plate exposed therefrom, said other surface being on the reverse side of the above-mentioned one surface; a yttrium oxide film provided on the above-mentioned one surface and the part of the other surface of the conductor plate, said part being exposed from the resin sealing part; and an insulating film that is provided on the yttrium oxide film. This power semiconductor module is also characterized in that the yttrium oxide film is formed of yttrium oxide crystals composed of cubic crystals and monoclinic crystals, with the ratio of the monoclinic crystals being 7% or less, and has a diffuse reflectance of 80% or less at a wavelength of 750 nm.