Ball grid array rework

Patent metadata

Field	Value
Publication number	US-9978706-B2
Application number	US-201615069435-A
Country	US
Kind code	B2
Filing date	Mar 14, 2016
Priority date	Jul 7, 2014
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

Embodiments relate to a method and apparatus 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.

First claim

We claim:

1. A method comprising:
placing a material between a ball grid array (BGA) package and a printed circuit board;
stimulating the material, the stimulation expanding the material and increasing separation between the BGA package and the printed circuit board; and
the expansion separating one or more solder joints between the BGA and the printed circuit board.

2. The method of claim 1 , wherein the stimulation is by a thermal stimulus.

3. The method of claim 1 , wherein the material is placed interstitially with respect to the one or more solder joints between the BGA package and the printed circuit board.

4. The method of claim 3 , further comprising delivering heat to the solder joints concurrent with stimulation of the material.

5. The method of claim 3 , further comprising the expansion elongating the solder joints.

6. The method of claim 1 , wherein the material is placed around a perimeter of the one or more solder joints between the BGA package and the printed circuit board.

7. The method of claim 6 , further comprising delivering heat to the one or more solder joints concurrent with stimulation of the material.

8. The method of claim 6 , further comprising the expansion elongating the one or more solder joints.

9. The method of claim 1 , wherein the material is selected from the group consisting of: a memory shape alloy and a high z-axis coefficient of thermal expansion material.

Assignees

• IBM

Inventors

• Kline Eric V
• Sinha Arvind K

Classifications

• H10W90/724

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W72/07254

  changes in dispositions · CPC title

• H10W72/248

  Top-view layouts, e.g. mirror arrays · CPC title

• H10W72/071

  Connecting or disconnecting · CPC title

• H05K1/11 Primary

  Printed elements for providing electric connections to or between printed circuits · CPC title