US Patent 11056426 Metallization interconnect structure formation

Techniques for fabricating a metallic interconnect include forming a first metallization layer that includes a first dielectric layer, a first metallic layer formed in the first dielectric layer and a first capping layer formed on the first dielectric layer and the first metallic layer and forming a second metallization layer that includes a second dielectric layer, a second metallic layer formed in the second dielectric layer and a second capping layer formed on the second dielectric layer and the second metallic layer. A channel is etched in the second capping layer, second dielectric layer, and first capping layer that exposes a portion of the first metallic layer and a portion of the second metallic layer. A metallic interconnect structure is formed in the channel in contact with the exposed portion of the first metallic layer and the exposed portion of the second metallic layer.