Selective TSV formation by local opening of almost through-silicon macropores. (a) Electrochemical etching of silicon leading to high aspect ratio structures. (b) Selective opening of the backside oxide mask followed by alkaline etching. This leads to local formation of through-silicon macropores. (c) Seed layer deposition on the backside. (d) Copper electrochemical deposition into the through-silicon macropores.
Defforge et al. Nanoscale Research Letters 2012 7:375 doi:10.1186/1556-276X-7-375