Patent ID: 6982225

Claim:
A method of making an interposer, comprising: forming an oxide layer on each of a first surface and a second surface of a substrate; patterning the oxide layer of the first surface to expose a first portion and a second portion of the substrate; isotropically etching through the first portion of the exposed substrate to form a first portion of at least one deep-via opening; anisotropically etching through the second portion of the exposed substrate to form a second portion of the at least one deep-via opening; growing an oxide layer on inner surfaces of the at least one deep-via opening; sputtering a copper barrier layer and a copper seed layer into the first and second portions of the at least one deep-via opening after growing the oxide layer; electroplating a conductive material over the seed layer to form the at least one deep-via; and forming vias and interconnect lines over the second surface of the substrate.