Self-aligned patterning of plate lines in three-dimensional ferroelectric capacitors

A method of forming a three-dimensional ferroelectric capacitor structure, comprising:

• forming a material stack comprising a first sacrificial layer, a second sacrificial layer above the first sacrificial layer, and a dielectric material above the first sacrificial layers and the second sacrificial layer;
• forming a first metal via connected to the first sacrificial layer and a second metal via connected to the second sacrificial layer;
• forming a third metal via with a ferroelectric material surrounding the third metal via;
• forming a hard mask above the first metal via, the second metal via, and the third metal via using a directed self-assembly (DSA) process;
• etching the material stack to expose side areas of the first sacrificial layer and the second sacrificial layer;
• removing the first sacrificial layer and the second sacrificial layer;
• and
• depositing metal in place of the removed first sacrificial layer and second sacrificial layer.

A method of forming a three-dimensional ferroelectric capacitor structure, comprising:

• forming a material stack comprising alternating layers of sacrificial material and dielectric material;
• forming metal vias in the material stack;
• forming a ferroelectric material around each respective metal via;
• forming a hard mask adjacent the metal vias;
• etching the material stack to expose the sacrificial material layers;
• removing the sacrificial material;
• depositing metal in place of the removed sacrificial material;
• and
• depositing a dielectric in areas of the material stack not covered by the hard mask.