Distortion free 3 point vacuum fixture
Spinner chuck Patent #: 4603867
ApplicationNo. 06/868875 filed on 05/23/1986
US Classes:156/285, Direct application of vacuum or fluid pressure during bonding228/4.5, Wire lead bonder269/21, Vacuum-type holding means279/3VACUUM
ExaminersPrimary: Ball, Michael W.
Assistant: Hoch, Ramon R.
Attorney, Agent or Firm
International ClassesH01L 21/67 (20060101)
H01L 21/683 (20060101)
AbstractA vacuum chuck for securely holding integrated circuit hybrid package substrates in fixed relationship to an X/Y table that is subjected to severe repeated lateral acceleration and decceleration forces to prevent appreciable lateral displacement of the package substrate relative to the X/Y table. A plurality of shallow, closed loop grooves are disposed in the chuck. A resilient O ring is disposed in each groove and normally extends a small but precise amount above the surface of the base. A vacuum path opens into each region circumscribed by an O ring. When a package substrate is positioned on an O ring and the vacuum then is applied, the O ring is compressed, causing the sides of the O ring to tightly engage the walls of the groove, preventing the O ring from "rolling" in the groove as a result of lateral acceleration and decceleration forces on the package. The compression increases the contact area between the O ring and the package substrate to produce sufficient friction to prevent lateral movement of the package substrate relative to the O ring. The vacuum chuck, used in conjunction with an automated wire bonding machine and an automated die bonding machine, allows rapid loading of multiple hybrid integrated circuit package substrates on the vacuum chuck.