Semiconductor device and manufacturing method of the same

Abstract

As means for preventing a leakage of a fuse element cut by laser trimming due to a conductive residue or the like, an insulating film which has a high thermal conductivity and a relatively low adhesion is formed between an element isolation region and the fuse element in the case of forming the fuse element on the element isolation region in a groove on a main surface of an epitaxial substrate. When the fuse element is cut by performing the laser trimming, both of a part of the fuse element and the insulating film below the part of the fuse element are removed.

1 - 10 . (canceled) 
     
     
         11 . A manufacturing method of a semiconductor device, comprising the steps of:
 (a) preparing a semiconductor substrate;   (b) forming a first insulating film on the semiconductor substrate;   (c) forming a second insulating film on the first insulating film; and   (d) forming a conductive film containing silicon on the second insulating film,   wherein the conductive film constitutes a fuse, and   the second insulating film has a thermal conductivity higher than that of the first insulating film.   
     
     
         12 . The manufacturing method of a semiconductor device according to  claim 11 ,
 wherein adhesion of the second insulating film to the first insulating film is lower than adhesion of a silicon film to the first insulating film.   
     
     
         13 . The manufacturing method of a semiconductor device according to  claim 11 , further comprising the step of:
 (b1) prior to the step (c), forming a groove on an upper surface of the first insulating film,   wherein in the step (c), a part of the second insulating film is buried in the groove.   
     
     
         14 . The manufacturing method of a semiconductor device according to  claim 13 ,
 wherein in the step (b1), the groove is formed by anisotropic etching.   
     
     
         15 . The manufacturing method of a semiconductor device according to  claim 11 , further comprising the steps of:
 (e) forming a third insulating film on the conductive film; and   (f) forming an opening, which penetrates through a stacked film made up of the second insulating film, the conductive film and the third insulating film, by performing laser irradiation to the conductive film, thereby cutting the fuse,   wherein an upper surface of the first insulating film is exposed on a bottom surface of the opening.