Structure and method for a low-K dielectric with pillar-type air-gaps

A method of fabricating an integrated circuit, the method comprising:

• receiving a substrate;
• depositing a sacrificial layer over the substrate, wherein the sacrificial layer comprises a polyimide;
• depositing a copolymer material over the sacrificial layer, wherein the copolymer material is directed self-assembling;
• inducing microphase separation within the copolymer material, wherein the inducing of the microphase separation defines a first region and a second region;
• selectively etching the sacrificial layer within the first region;
• depositing a dielectric material within the first region to define an interlayer dielectric structure;
• selectively etching the sacrificial layer and the dielectric material, wherein the selectively etching defines a third region;
• depositing a conductive material within the third region to define an interconnect structure;
• and
• removing the sacrificial layer from the second region to form an air gap within the interlayer dielectric structure.

A method comprising:

• receiving a substrate having a first material layer disposed thereupon, wherein the first material layer comprises a polyimide;
• depositing a copolymer material over the first material layer;
• inducing a separation of the copolymer material into two or more different polymers;
• selectively removing at least one of the two or more different polymers to form a pattern In the copolymer material that remains;
• transferring the pattern in the copolymer material to the first material layer by removing at least one portion of the first material layer;
• depositing a second material layer within the first material layer after the transferring of the pattern in the copolymer material;
• selectively etching a region of the first and second material layers;
• and
• depositing a third material layer within the selectively etched region of the first and second material layers.