Semiconductor device having air gap and method for manufacturing the same

A method for manufacturing a semiconductor device, comprising:

• forming a conductive interconnect structure over a substrate, the conductive interconnect structure including a dielectric layer and a first conductive interconnect disposed in the dielectric layer;
• forming a plurality of second conductive interconnects on the conductive interconnect structure, the plurality of the second conductive interconnects being spaced apart from each other so as to form a plurality of trenches among the plurality of the second conductive interconnects, the first conductive interconnect being electrically connected to a corresponding one of the plurality of the second conductive interconnects;
• forming a plurality of functionalized molecules such that the plurality of functionalized molecules are bonded to an upper surface of the dielectric layer so as to form a self-assembled monolayer filled in the plurality of the trenches;
• subjecting the plurality of the functionalized molecules to a rearrangement treatment so as to permit the plurality of the functionalized molecules to be evenly bonded on the upper surface of the dielectric layer;
• forming an etch stop layer on the plurality of the second conductive interconnects and the self-assembled monolayer;
• and
• removing the self-assembled monolayer to form a plurality of air gaps so that two adjacent ones of the plurality of the second conductive interconnects are spaced apart from each other by a corresponding one of the plurality of the air gaps.

A method for manufacturing a semiconductor device, comprising:

• forming a conductive interconnect structure over a substrate, the conductive interconnect structure including a plurality of first conductive interconnects spaced apart from each other;
• forming a dielectric layer over the conductive interconnect structure;
• forming a plurality of second conductive interconnects which are spaced apart from each other and which protrude upwardly from an upper surface of the dielectric layer, so as to form a plurality of trenches among the plurality of the second conductive interconnects, one of the plurality of the second conductive interconnects penetrating the dielectric layer and being electrically connected to a corresponding one of the plurality of the first conductive interconnects;
• forming a plurality of functionalized molecules such that the plurality of functionalized molecules are bonded to the upper surface of the dielectric layer so as to form a self-assembled monolayer filled in the plurality of the trenches;
• subjecting the plurality of the functionalized molecules to a rearrangement treatment so as to permit the plurality of the functionalized molecules to be evenly bonded on the upper surface of the dielectric layer;
• forming an etch stop layer on the plurality of the second conductive interconnects and the self-assembled monolayer;
• and
• removing the self-assembled monolayer to form a plurality of air gaps so that two adjacent ones of the plurality of the second conductive interconnects are spaced apart from each other by a corresponding one of the plurality of the air gaps.