Semiconductor device having a discontinued part between a first insulating film and second insulating film

Abstract

A semiconductor device, in which an increase in the size of a product can be suppressed and a withstand voltage between wiring layers can be improved, and a manufacturing method thereof are provided. A discontinued part, in which the interface between an interlayer insulating film and a passivation film is discontinued, is formed between a first wiring layer and a second wiring layer that are adjacent to each other with a space therebetween. Both the interlayer insulating film and the passivation film face an air gap in the discontinued part.

What is claimed is: 
     
         1 . A semiconductor device comprising:
 a first insulating film;   a first wiring and a second wiring formed on the first insulating film;
 a second insulating film formed on the first insulating film, the first wiring, and the second wiring; and 
 a discontinued part, in which, an interface between the first insulating film and the second insulating film is discontinued, formed between the first wiring and the second wiring. 
   
     
     
         2 . The semiconductor device according to  claim 1 , wherein the discontinued part is formed by an air gap. 
     
     
         3 . The semiconductor device according to  claim 2 ,
 wherein a trench is formed in the first insulating film, and the air gap is formed in the trench with the second insulating film blocking the trench.   
     
     
         4 . The semiconductor device according to  claim 2 , further comprising a third insulating film formed over the second insulating film,
 wherein a trench is formed in the first insulating film, and the air gap is formed in the trench with the third insulating film blocking the trench.   
     
     
         5 . The semiconductor device according to  claim 1 ,
 wherein the first insulating film and the second insulating film are comprised of respective materials different from each other.   
     
     
         6 . The semiconductor device according to  claim 5 ,
 wherein one of the first insulating film and the second insulating film includes silicon oxide, and the other of them includes silicon nitride.   
     
     
         7 . The semiconductor device according to  claim 1 ,
 wherein the first insulating film and the second insulating film are comprised of the same material as each other.   
     
     
         8 . The semiconductor device according to  claim 2 , further comprising a dummy wiring arranged between the first wiring and the second wiring,
 wherein the discontinued part and the air gap are located between at least one of the first wiring and the second wiring and the dummy wiring layer.   
     
     
         9 . The semiconductor device according to  claim 8 ,
 wherein the dummy wiring layer surrounds whole circumference of at least one of the first wiring and the second wiring.   
     
     
         10 . The semiconductor device according to  claim 2 ,
 wherein the air gap surrounds whole circumference of each of the first wiring and the second wiring.   
     
     
         11 . The semiconductor device according to  claim 10 ,
 wherein the air gap is continuously extended to surround whole circumference of each of the first wiring and the second wiring.   
     
     
         12 . The semiconductor device according to  claim 10 ,
 wherein the air gap is intermittently extended to surround whole circumference of each of the first wiring and the second wiring.   
     
     
         13 . The semiconductor device according to  claim 1 ,
 wherein each of the first wiring and the second wiring is an uppermost wiring of multi-layer wiring.   
     
     
         14 . The semiconductor device according to  claim 1 ,
 wherein the first wiring is one transformer that forms a microisolator, and   the second wiring is the other transformer that forms the microisolator.   
     
     
         15 . A semiconductor device comprising:
 a first insulating film;   a first wiring and a second wiring embedded in the first insulating film;
 a second insulating film formed on the first insulating film, the first wiring, and the second wiring; 
 a discontinued part, in which an interface between the first insulating film and the second insulating film is discontinued, formed between the first wiring and the second wiring. 
   
     
     
         16 . The semiconductor device according to  claim 15 , wherein the discontinued part is formed by an air gap. 
     
     
         17 . The semiconductor device according to  claim 15 ,
 wherein the second insulating film includes a diffusion prevention film and a fourth insulating film.   
     
     
         18 . The semiconductor device according to  claim 16 ,
 wherein a trench is formed in the first insulating film, and the air gap is formed in the trench with the fourth insulating film blocking the trench.   
     
     
         19 . The semiconductor device according to  claim 15 ,
 wherein the first wiring and the second wiring include a copper.   
     
     
         20 . The semiconductor device according to  claim 15 ,
 wherein a barrier metal layer is formed between the first insulating film and the first wiring.