| 摘要 |
PROBLEM TO BE SOLVED: To provide a substrate for a power module, in which the occurrence of delamination is prevented.SOLUTION: A substrate for a power module comprises: a circuit layer; a metal layer; and a ceramic base on which the circuit layer and the metal layer are laminated. The circuit layer has: a first aluminum layer bonded to one face of the ceramic base; and a first copper layer bonded to the first aluminum layer by solid-phase diffusion. The metal layer has: a second aluminum layer bonded to the other face of the ceramic base; and a second copper layer bonded to the second aluminum layer by solid-phase diffusion. At least one copper layer of the first and second copper layers has notches, which is obtained by removing corresponding surface portions of the at least one copper layer to a depth of 50-95% of the thickness thereof, and which is provided in end portions of the at least one copper layer corresponding to two ends of a bonding plane of the circuit or metal layer having the at least one copper layer and the ceramic base in its longitudinal direction. Supposing that a half of the length of the bonding plane of the circuit or metal layer having the at least one copper layer in the longitudinal direction is L, and the width of each notch of the bonding plane along the longitudinal direction is W, the ratio (W/L) of W to L is 0.02-0.27.SELECTED DRAWING: Figure 1 |
