Ball grid array rework
View Patent ↗Embodiments of the invention relates to a method for rework of a BGA package. Memory shape material is placed adjacent to a plurality of solder joints of the package. Stimulation is applied to the material, with the stimulation causing the material to change from a non-stimulated shape to a stimulated shape. This stimulation causes an expansion of the material. As the material expands, it exerts a tensile force on the BGA package and an adjacently positioned carrier, causing a separation of the two components, while mitigating collateral heat of adjacently positioned components.
1. A method comprising:
placing an expansion material between a ball grid array (BGA) package assembled in communication with a printed circuit board, including the expansion material placed interstitially within a matrix of solder joints between the BGA package and the printed circuit board;
controlling a tensile force applied between a ball grid array (BGA) package and the printed circuit board, including delivering electric current to the expansion material; and
the electric current creating localized heating of the expansion material;
the heated material applying an expansion force to the solder joints, including separation of the BGA package from the printed circuit board.
2. The method of claim 1 , further comprising the expansion force elongating the solder joints substantially into two parts, including a first part remaining in communication with the BGA package and a second part remaining in communication with the printed circuit board.
3. The method of claim 1 , wherein the expansion material is selected from the group consisting of: a memory shape alloy and a high z-axis coefficient of thermal expansion material.
4. The method of claim 1 , further comprising aligning the material in parallel across the matrix, including positioning parallel placements of the material between BGA package solder joints.
5. The method of claim 1 , further comprising delivering heat from an external source to the solder joints concurrent with delivery of the electric current to the material.
6. A method comprising:
configuring a ball grid array (BGA) package assembled on to a printed circuit board;
placing an expansion material between the BGA package and the printed circuit board, including the expansion material placed within a matrix of solder joints;
applying an expansion to the material, the expansion creating a tensile force between the BGA package and the printed circuit board; and
the tensile force causing a separation of the BGA package from the printed circuit board.
7. The method of claim 6 , wherein the expansion material is selected from the group consisting of: a memory shape alloy and a high z-axis coefficient of thermal expansion material.
8. The method of claim 6 , further comprising aligning the material in parallel across the matrix, including positioning parallel placement of the material between BGA package solder joints.
9. The method of claim 6 , further comprising delivering electric current to the material, and an exothermic reaction from the material displacing the material and deforming the solder joints.
10. The method of claim 9 , further comprising the material displacement creating a force tearing the solder joints between the BGA package and the printed circuit board.
11. The method of claim 9 , further comprising delivering heat from an external source to the solder joints concurrent with delivery of the electric current to the material.
12. The method of claim 9 , further comprising and controlling the material expansion, including controlling delivery of the current to the material.