US 10,433,429 B2
Method of enhancing fatigue life of grid arrays
James H. Kelly, West Newbury, MA (US); Dmitry Tolpin, Sharon, MA (US); and Roger M. Maurais, Goffstown, NH (US)
Assigned to Massachusetts Institute of Technology, Cambridge, MA (US)
Filed by Massachusetts Institute of Technology, Cambridge, MA (US)
Filed on Sep. 20, 2016, as Appl. No. 15/270,940.
Application 15/270,940 is a division of application No. 13/901,398, filed on May 23, 2013, granted, now 9,491,859.
Claims priority of provisional application 61/650,602, filed on May 23, 2012.
Prior Publication US 2017/0013725 A1, Jan. 12, 2017
Int. Cl. H05K 3/30 (2006.01); H05K 1/11 (2006.01); H05K 1/18 (2006.01); H05K 3/34 (2006.01)
CPC H05K 3/301 (2013.01) [H05K 1/111 (2013.01); H05K 1/18 (2013.01); H05K 1/181 (2013.01); H05K 3/30 (2013.01); H05K 3/303 (2013.01); H01L 2224/16225 (2013.01); H01L 2924/10253 (2013.01); H01L 2924/351 (2013.01); H01L 2924/381 (2013.01); H05K 3/3436 (2013.01); H05K 2201/068 (2013.01); H05K 2201/094 (2013.01); H05K 2201/09418 (2013.01); H05K 2201/09427 (2013.01); H05K 2201/10242 (2013.01); Y02P 70/611 (2015.11); Y10T 29/4913 (2015.01); Y10T 29/49133 (2015.01)] 12 Claims
OG exemplary drawing
 
1. A method of assembling an electronic component onto a printed circuit board comprising:
providing the printed circuit board having a printed circuit board coefficient of thermal expansion;
placing an array of pads on the printed circuit board;
applying connective material to the array of pads;
providing the electronic component, having an array of conducting posts and a different coefficient of thermal expansion than the printed circuit board coefficient of thermal expansion;
placing the electronic component on the printed circuit board so that the array of conducting posts of the electronic component is misaligned with the array of pads;
mounting the electronic component to the printed circuit board by heating the connective material and positioning the array of conducting posts against the connective material on the array of pads with ends of conducting posts of the array of conducting posts being drawn into closer alignment with pads of the array of pads wherein the conducting posts of the array of conducting posts have an angular tilt outwardly away from a center of the electronic component to the printed circuit board; and
maintaining the angular tilt outward of the array of conducting posts outwardly away from a center of the electronic component to the printed circuit board to a sufficient degree due to sufficient misalignment of the conducting posts with the array pads of the printed circuit board at 20 degrees Celsius and over a temperature range of 0 degrees Celsius to 100 degrees Celsius.