Patent ID: 7356907

Claim:
A method of manufacturing a cartridge assembly of a hard disk drive, comprising: a step of forming a part of a wiring circuit, which is electrically connected to a magnetic head mounted on an end of a long tail suspension circuit board, into flying leads; a step of forming a coating layer, which is made of a thermally meltable metal whose melting point is lower than that of a material constituting bonding surfaces, on the respective opposite surfaces of the bonding surfaces of the flying leads, which will be connected to bonding terminals of a flexible printed circuit board; a step of placing an ultrasonic tool in contact with the opposite surfaces of the flying leads via the coating layers, and applying ultrasonic vibration from the ultrasonic tool in a state where the flying leads are pressed onto the bonding terminals to ultrasonically bond the flying leads and the bonding terminals together; and a step of heating and melting the coating layers to smooth surfaces of the coating layers that have been roughened by contact with the ultrasonic tool during ultrasonic bonding.