PURPOSE: A substrate for a power module is provided to efficiently transmit heat by using a metal base substrate made of and a multilayered ceramic filler layer. CONSTITUTION: An insulating layer (120) is formed on a metal base substrate. The insulating layer includes a ceramic filler layer (123). The ceramic filler layer is formed at the bonding interface between multilayered insulation bonding layers. A circuit layer is formed on the insulating layer. The ceramic filler layer includes uniform ceramic fillers distributed on the total surface of the bonding interface.
