Precision Chip Positioning by Footprint
Original Publication Date: 1983-Aug-01
Included in the Prior Art Database: 2005-Feb-07
Positioning a chip by using the chip's footprint (solder ball pattern), rather than the present technique of locating using an edge of the chip, provides a much more precise method for chip placement. The accuracy is maintained from lot to lot with no adjustments necessary due to irregularities in the dicing of the chips. The chip-locating device, shown in Figs. 1a and 1b, consists of the precision nest 1, which in most cases uses a V-groove pattern 8 to locate the chip 6 by means of the solder balls 7. The chip 6 is transported in the nest 1 by means of a built-in air track. The chips 6 enter the air track and the nest 1 one at a time from a chip storage device, such as a helix or linear track.