Patent ID: 8723319

Claim:
A Ball Grid Array (BGA) structure, comprising: a substrate having a first surface used to carry a chip and a second surface opposite to the first surface, wherein the substrate is divided, from a central point of the substrate, into several regions consisting of a first region, a second region, and a third region, and wherein the substrate is divided according to a density of semiconductor devices in each region of the first region, the second region, and the third region; and according to a total area of the substrate having the first region distance from the central point of the substrate for at least about 0 mm to about 15 mm; a plurality of contact bonding pads on the second surface electrically connected with the chip; and a plurality of bumps respectively attached to each of the contact bonding pads, wherein the plurality of bumps have a same height, and wherein the contact bonding pads and bumps in the first region at the central point and closest to the central point of the substrate have a smallest diameter, while the contact bonding pads and bumps in the third region farthest to the central point of the substrate have a biggest diameter.