Patent ID: 7350684

Claim:
A bump formation method for forming bumps to electrode parts on a semiconductor substrate which is at a bump bonding temperature at which bumps are formed to electrode parts, the method comprising: before the bumps are formed to the electrode parts, executing a pre-formation temperature control for bonding promotion to the semiconductor substrate to improve bonding between the electrode parts and the bumps during a bump formation, the pre-formation temperature control being performed in manner so as to change a particle size of metal particles of the electrode parts of the semiconductor substrate from larger original-size particles to smaller fine-size particles, and being performed while the semiconductor substrate is in contact with a heating part for heating the semiconductor substrate, the pre-formation temperature control comprising: heating the semiconductor substrate to a pre-formation temperature for bonding promotion which is 30° C. to 60° C. greater than the bump bonding temperature and is not higher than a damage preventive temperature of the semiconductor substrate, maintaining the semiconductor substrate at the pre-formation temperature for bonding promotion for a pre-formation length of time for bonding promotion, and setting the semiconductor substrate to the bump bonding temperature after lapse of the pre-formation length of time for bonding promotion; and after the pre-formation temperature control, forming the bumps to the electrode parts on the semiconductor substrate.