Bonding Capillaries Bonding Evolution 2018 by SPT - Small Precision Tools

More catalogs by SPT - Small Precision Tools | Bonding Capillaries Bonding Evolution 2018 | 41 pages | 2018-02-19


Page 14 of Bonding Capillaries Bonding Evolution 2018

gold copper wire bonding cycle 3 ball bond formation the capillary is lowered with the free air ball at its tips’ center and initial ball deformation is made by the application of impact force the application of the ultrasonic energy force temperature and time enabled the initial ball to be deformed further to the geometrical shape of inside chamfer chamfer angle and the hole 4 capillary forms the loop and then stitch bond after the ball bonding the capillary raises looping takes place as the capillary travels at the same time from the first position of the ball bond to the direction of the second bond to form the stitch the looping can be varied to a different modes depending upon the device package type achieving low-loop long lead bonding is no more a problem because of the programmable looping algorithm that optimizes its formation for each different lead length 5 tail formation after the stitch bond once the capillary reaches the targeted second bond position the stitch is then formed with similar factors applied during the first bond the capillary deformed the wire against the lead or substrate producing a wedge-shaped impression 6 capillary lifts and forms a tail it is important to note that a certain amount of tail bond is left to allow pulling of the wire out of the capillary after the stitch bond application in preparation for the next free-air-ball formation back to content 14