Interconnect structure

Abstract

Various embodiments provide interconnect structures and fabrication methods. A carbon-containing dielectric layer can be formed on a substrate. A protective layer can be formed on the carbon-containing dielectric layer to prevent carbon loss from the carbon-containing dielectric layer by performing a surface treatment to the carbon-containing dielectric layer using a gas at least containing silicon and hydrogen. A hard mask layer can be formed on the protective layer. A through hole can be formed in the carbon-containing dielectric layer using the hard mask layer as a mask to expose a surface of the substrate for forming a contact plug in the through hole.

1 .- 14 . (canceled) 
     
     
         15 . An interconnect structure, comprising:
 a carbon-containing dielectric layer disposed on a substrate;   a protective layer disposed on the carbon-containing dielectric layer to prevent carbon loss from the carbon-containing dielectric layer, wherein the protective layer is formed by a surface treatment to the carbon-containing dielectric layer using a gas at least containing silicon and hydrogen; and   a hard mask layer disposed on the protective layer, wherein the carbon-containing dielectric layer includes a through hole using the hard mask layer as a mask and the through hole exposes a surface of the substrate for forming a contact plug in the through hole.   
     
     
         16 . The interconnect structure of  claim 15 , wherein the carbon-containing dielectric layer is a low-K dielectric layer or an ultra-low-K dielectric layer. 
     
     
         17 . The interconnect structure of  claim 15 , wherein the carbon-containing dielectric layer is made of a material including SiCOH, SiCO, SiCON, or a combination thereof. 
     
     
         18 . The interconnect structure of  claim 15 , wherein the protective layer is made of a material including C, Si, H, O, or a combination thereof. 
     
     
         19 . The interconnect structure of  claim 15 , wherein the gas containing silicon and hydrogen includes silane. 
     
     
         20 . The interconnect structure of  claim 15 , wherein the hard mask layer is made of a material including silicon oxide. 
     
     
         21 . The interconnect structure of  claim 15 , wherein the carbon-containing dielectric layer includes a UV-treated dielectric material by ultraviolet (UV) light in a UV-treatment chamber. 
     
     
         22 . The interconnect structure of  claim 15 , wherein the carbon-containing dielectric layer is formed by a diethoxymethylsilane and atom transfer radical polymerization. 
     
     
         23 . The interconnect structure of  claim 15 , wherein the carbon-containing dielectric layer is made of black diamond.