摘要 |
A PBGA package includes PBGA member, a stiffener ring, and a stiffener fixture which includes a retaining recess having a floor for receiving the stiffener ring and includes a ledge positioned above the recess floor for receiving the PBGA member. An adhesive layer is applied to the stiffener ring, which is adhered to the PBGA member. The stiffener ring and PBGA member are essentially coplanar to less than 8 mils. A top plate is placed on top of the PBGA member and the ring and member are secured together tightly. |