Power semiconductor module

Abstract

To suppress warpage of a ceramic substrate, and to prevent a reduction in radiation efficiency. A power semiconductor module includes a module casing fitted with a radiator, and a common unit retained by the module casing. The common unit has: a ceramic substrate having a circuit surface disposed with a semiconductor element, and a radiation surface brought into abutting contact with the radiator; and a package formed by exposing the radiation surface and sealing the circuit surface with heat resistant resin. The circuit surface and the radiation surface are respectively formed of metal layersformed on the ceramic substrate, and the metal layerforming the radiation surface has: by forming a buffer patternincluding a groove part extending along a circumferential part thereof, a radiation patternformed on an inner side of the buffer pattern; and an outer peripheral patternformed on an outer side of the buffer pattern. Such a configuration enables warpage of the ceramic substrate to be suppressed, and a reduction in radiation efficiency to be prevented.