Patent ID: 8592976
Filing Date: 2013-11-26
Classification: H01L

Abstract:
1. A structure, comprising: a first dielectric layer which includes a top dielectric surface; an electrically conductive line in the first dielectric layer; a second dielectric layer on the first dielectric layer and the electrically conductive line; a continuous ball-limiting-metallurgy (BLM) region on the second dielectric layer and the electrically conductive line, wherein the BLM region is electrically connected to the electrically conductive line, wherein the BLM region defines multiple vias whose sidewalls are distinct portions of the BLM region, and wherein the sidewalls are oriented perpendicular to the top dielectric surface; and a solder ball on the BLM region and filling the multiple vias defined by the BLM region, wherein the solder ball comprises an electrically conductive solder material continuously distributed throughout the solder ball and capable of being reflowed, wherein the solder ball is electrically connected to the BLM region, wherein the BLM region has a characteristic that a length of the longest straight line segment of at least five coplanar straight line segments which are parallel to the top dielectric surface and which are entirely in the BLM region does not exceed a pre-specified maximum value, wherein the pre-specified maximum value is at most one-half of a maximum horizontal dimension of the BLM region measured in a horizontal direction parallel to the top dielectric surface, and wherein the at least five coplanar straight line segments are in direct physical contact with the second dielectric layer.