Ceramic circuit substrate and its production method
A method for producing a ceramic circuit substrate comprising the steps of forming brazing regions each comprising brazing material powder and an organic binder on a ceramic substrate; setting metal plates on the ceramic substrate via the brazing regions, and heating the ceramic substrate, the brazing regions and the metal plates to bond the metal plates to the ceramic substrate via brazing layers made of the brazing material, thereby forming a bonded body; and cleaning the bonded body with a hypochlorite-containing agent.
1. A method for producing a ceramic circuit substrate comprising the steps of:
forming brazing regions each comprising brazing material powder and an organic binder on a ceramic substrate;
setting metal plates on said ceramic substrate via said brazing regions, and heating said ceramic substrate, said brazing regions and said metal plates to bond said metal plates to said ceramic substrate via brazing layers made of said brazing material, thereby forming a bonded body; and
removing deposits of organic binder by cleaning said bonded body with a hypochlorite-containing agent,
wherein the method further comprises a step of forming a resist layer on said metal plates after the bonding step and before the cleaning step, a step of etching said metal plates to form circuit patterns, and then a step of removing residual brazing layers.
2. The method for producing a ceramic circuit substrate according to claim 1 , wherein the concentration of hypochlorite is 2.5-13.5% by mass as sodium hypochlorite.
3. The method for producing a ceramic circuit substrate according to claim 1 , wherein said agent has pH of 9 or more.
4. The method for producing a ceramic circuit substrate according to claim 1 , wherein said cleaning is conducted at 30° C. or higher for 5 minutes or more.