Bump-forming method using two plates and electronic device

A method of forming bumps comprising the steps of:

• filling a plurality of cavities of a first plate with metal paste by squeegeeing, and filling a plurality of cavities of a second plate arranged in a mirror symmetry relationship with said cavities of said first plate with metal paste by squeegeeing;
• setting said first plate and said second plate in a facing relationship with each other with said cavities of said first plate located in registry with said cavities of said second plate;
• heating said first and second plates to form metal balls in said cavities in one of said first and second plates;
• moving one of said first and second plates relative to the other of said first and second plates, and
• transferring the metal balls in said cavities in one of said first and second plates to a device on which bumps are to be formed.