Method for making a semiconductor device including a superlattice as a gettering layer

A semiconductor processing method comprising:

• forming a superlattice gettering layer on a front side of a semiconductor substrate having a first thickness, the superlattice gettering layer comprising a plurality of stacked groups of layers, each group of layers comprising a plurality of stacked base silicon monolayers defining a base silicon portion, and at least one oxygen monolayer constrained within a crystal lattice of adjacent base silicon portions;
• epitaxially growing an active semiconductor layer on the superlattice gettering layer opposite the semiconductor substrate;
• forming at least one semiconductor device in the active semiconductor layer;
• forming at least one metal interconnect layer on the active layer, and at least one metal through-via extending from the at least one metal interconnect layer into the semiconductor substrate;
• and
• thinning the semiconductor substrate from a back side thereof to a second thickness less than the first thickness;
• the superlattice gettering layer configured to getter metal ions released by the forming of the at least one metal interconnect layer and at least one metal through-via, and thinning the semiconductor substrate.

A semiconductor processing method comprising:

• forming a superlattice gettering layer on a front side of a semiconductor substrate having a first thickness, the superlattice gettering layer comprising a plurality of stacked groups of layers, each group of layers comprising a plurality of stacked base silicon monolayers defining a base silicon portion, and at least one oxygen monolayer constrained within a crystal lattice of adjacent base silicon portions;
• epitaxially growing an active semiconductor layer on the superlattice gettering layer opposite the semiconductor substrate, the active semiconductor layer having a thickness in a range of 2 to 5 μm;
• forming at least one semiconductor device in the active semiconductor layer;
• forming at least one metal interconnect layer on the active layer, and at least one metal through-via extending from the at least one metal interconnect layer into the semiconductor substrate;
• and
• thinning the semiconductor substrate from a back side thereof to a second thickness less than the first thickness, the second thickness being less than 200 μm;
• the superlattice gettering layer configured to getter metal ions released by the forming of the at least one metal interconnect layer and at least one metal through-via, and thinning the semiconductor substrate.