Semiconductor structure including a first rigid dielectric layer and a
second rigid dielectric layer. A first non-rigid low-k dielectric layer
is formed between the first and second rigid dielectric layer. A
plurality of dummy fill shapes is formed in the first non-rigid layer
which replace portions of the first non-rigid low-k dielectric layer with
lower coefficient of thermal expansion (CTE) metal such that an overall
CTE of the first non-rigid low-k dielectric layer and the plurality of
dummy fill shapes matches a CTE of the first and second rigid dielectric
layers more closely than that of the first non-rigid low-k dielectric
layer alone.