Patent ID: 7901995
Filing Date: 2011-03-08
Classification: H01L,H05K,Y02P

Abstract:
1. A method for preparing a first device, say a Ball Grid Array (BGA) package or a chip, having a generally flat surface, and having at least a first and a second contact pads arranged along said flat surface, said contact pads of said first device being referred to as the BGA contact pads, to be subsequently attached to a second device, say a Printed Circuit Board (PCB) or a substrate, having a generally flat surface, and having at least a first and a second contact pads arranged along said flat surface, said contact pads of said second device being referred to as the PCB contact pads, said method comprising: resulting in a device with columnar leads, referred to as a dead roach or simply a roach, wherein said connecting elements comprise migration prevention means to prevent any joining materials, which may be present during step (b), which could be liquid or molten, from migrating away from the joints at said BGA ends of said connecting elements towards the center of said connecting elements along the stem of said connecting elements, and/or from attaching themselves to said stems.