Multi-step isotropic etch patterning of thick copper layers for forming high aspect-ratio conductors

An integrated circuit (IC) device, comprising:

• a substrate comprising a dielectric material;
• and
• a conductor within the dielectric material of the substrate, the conductor comprising:
• a first portion comprising a first base having a first base width, a first top having a first top width, and a first sloped sidewall from the first top to the first base, the first base width greater than the first top width, the first sloped sidewall in contact with the dielectric material;
• and
• a second portion over the first portion, the conductor comprising a conductive material, the conductive material continuous between and comprising the first and second portions, the second portion comprising a second base having a second base width, a second top having a second top width, and a second sloped sidewall from the second top to the second base, the second base width greater than the second top width, the second sloped sidewall in contact with the dielectric material, and an overhang from the second sloped sidewall to the first sloped sidewall.

An integrated circuit (IC) device, comprising:

• a substrate comprising a dielectric material;
• and
• a conductor on or within the dielectric material of the substrate, the conductor having a pagoda-like cross-section, the conductor comprising:
• a first portion comprising a first curved sidewall and a top of the first portion;
• and
• a second portion over the first portion, the second portion comprising a second curved sidewall, a base of the second portion, and an overhang over the first curved sidewall, wherein a second base width of the second portion is greater than a first top width of the first portion, and the overhang is from the first curved sidewall and the top of the first portion to the second curved sidewall and the base of the second portion.