Semiconductor apparatus, power module and power supply

A semiconductor apparatus comprising:

• a thermal source comprising a semiconductor device, the semiconductor device generating heat in an operating state;
• a thermal diffusion unit that is thermally connected to the thermal source and forms a space at a position opposite to the thermal source by means of a first portion extending from a connecting portion with the thermal source to both sides along a first direction parallel to a connecting surface with the thermal source and second and third portions respectively extending from both ends of the first portion in a second direction opposite to the thermal source;
• a first thermal conduction layer attached to a space-side surface of the second portion, and a second thermal conduction layer attached to a space-side surface of the third portion;
• a first heat dissipation unit that is attached to the first thermal conduction layer and has a first base unit and a plurality of first fin units arranged so as to extend in the space from the first base unit;
• and
• a second heat dissipation unit that is attached to the second thermal conduction layer and has a second base unit and a plurality of second fin units arranged so as to extend in the space from the second base unit.