Heterogeneous metallization using solid diffusion removal of metal interconnects

A method for forming trenches of an interconnect network in a substrate, the method comprising:

• forming a first trench of the trenches in the substrate, wherein the first trench comprises a first width dimension;
• forming a second trench of the trenches in the substrate, wherein the second trench comprises a second width dimension that is greater than the first width dimension;
• depositing a first metal layer into the first trench and the second trench;
• applying a dielectric layer over the first metal layer;
• and
• diffusing first metal atoms of the first metal layer from each of the first trench and the second trench to the dielectric layer, wherein the dielectric layer absorbs the first metal atoms from the first trench leaving the first trench devoid of significantly all of the first metal atoms while simultaneously absorbing only a minority of the first metal atoms from the second trench.