Cooling structure null of cooling body and circuit substrate for circuit substrate

摘要

PURPOSE:To obtain a circuit board cooling structure which is excellent in elasticity and rigidity and deteriorates hardly in flatness after a long-term service by a method wherein two metal boards of copper alloy specified in composition are made to overlap each other, a hollow cooling path is provided between the overlapped metal boards. CONSTITUTION:Two metal boards 3A and 3B are bonded together to form a cooling body 2, the metal board 3b is made to protrude partially to form a cavity semicircular in cross section between the boards 3A and 3B, a coolant path 4 is provided to the cavity, and the coolant path 4 is formed into a meandering shape provided with linear parts in parallel. The flat metal board 3A out of the two metal boards 3A and 3B is formed of copper alloy composed of 0.05-3% by weight of Fe, 0.01-0.15% by weight of P, and the residual % by weight of Cu. On the other hand, it is preferable that the metal board 3B is formed of pure copper excellent in thermal conductivity and molding property.