Methods for forming a via and a conductive path are disclosed. The methods
include forming a via within a wafer with cyclic etch/polymer phases,
followed by an augmented etch phase. The resulting via may include a
first portion having a substantially uniform cross-section and a second
portion in the form of a hollow ball, extending laterally further within
the wafer than the first portion. Back-grinding the wafer to the second
portion of the via may create a vent. A conductive path may be formed by
filling the via with a conductive material, such as solder. Flux gases
may escape through the vent. The wafer surrounding the second portion of
the via may be removed, exposing a conductive element in the shape of a
ball, the shape of the second portion of the via. Semiconductor devices
including the conductive paths of the present invention are also
disclosed.