Semiconductor device having air gap and method for manufacturing the same

A semiconductor device, comprising:

• a substrate;
• a conductive interconnect structure disposed on the substrate;
• a glue layer disposed on the conductive interconnect structure opposite to the substrate;
• metal lines disposed on the glue layer opposite to the conductive interconnect structure;
• protective layers respectively covering lateral surfaces of the metal lines, one of the protective layers including functional groups, one of the functional groups being represented by formula (A):
• wherein R1, R2, and R3 are each independently a methoxy group, a thiol group, or a dihydrogen phosphate group with the proviso that at least one of R1, R2, and R3 is the methoxy group;
• air gaps formed among the metal lines such that two adjacent ones of the metal lines are spaced apart from each other by at least one of the air gaps;
• and
• an interlayer dielectric layer disposed on the conductive interconnect structure and cooperating with the conductive interconnect structure and the protective layers to define the air gaps.

A semiconductor device, comprising:

• a substrate;
• a first dielectric layer disposed on the substrate;
• an electrically conductive interconnect disposed in the first dielectric layer;
• metal lines disposed on the first dielectric layer opposite to the substrate, one of the metal lines being electrically connected to the electrically conductive interconnect;
• protective layers respectively covering lateral surfaces of the metal lines, one of the protective layers including functional groups, one of the functional groups being represented by formula (A):
• wherein R1, R2, and R3 are each independently a methoxy group, a thiol group, or a dihydrogen phosphate group with the proviso that at least one of R1, R2, and R3 is the methoxy group;
• air gaps formed among the metal lines such that two adjacent ones of the metal lines are spaced apart from each other by at least one of the air gaps;
• and
• a second dielectric layer disposed on the first dielectric layer and cooperating with the first dielectric layer and the protective layers to define the air gaps.