In order to meet the use function and working environment of ceramic substrate,the technical requirements of copper cladding process are as follows:

• ■ Thermal conductivity requirements: copper and ceramic substrate brazing 100% compactness, no cavity;
• ■ Reliability requirements: high welding strength, no cracking or failure in the specified number of cold and heat cycles;
• ■ Voltage level requirements: suitable ceramic board thickness and circuit gap width, circuit gap groove bottom etched clean, meet the required insulation strength.
• ■ Surface treatment requirements: ensure the solderability and oxidation resistance of copper conductor. Ensure to meet the ultrasonic bonding strength of aluminum wire.