| US 7,531,891 B2 | ||
| Semiconductor device | ||
| Koichi Ohto, Kawasaki (Japan); Tatsuya Usami, Kawasaki (Japan); and Yoichi Sasaki, Kawasaki (Japan) | ||
| Assigned to NEC Electronics Corporation, Kanagawa (Japan) | ||
| Filed on Dec. 08, 2004, as Appl. No. 11/6,529. | ||
| Claims priority of application No. 2004-027158 (JP), filed on Feb. 03, 2004. | ||
| Prior Publication US 2005/0167844 A1, Aug. 04, 2005 | ||
| Int. Cl. H01L 23/58 (2006.01); H01L 29/00 (2006.01); H01L 21/31 (2006.01) | ||
| U.S. Cl. 257—634 [257/635; 257/650; 257/655; 257/E21.277; 438/758; 438/787; 438/789; 438/931] | 13 Claims |
| 1. A semiconductor device, comprising:
a semiconductor substrate; and
an interlayer insulating film on said semiconductor substrate,
wherein said interlayer insulating film includes a multilayered film having a first insulating film and a second insulating
film directly contacting and having a lower film density than said first insulating film, and
wherein said second insulating film includes a first density transition region, said first density transition region having
a film density distribution profile in which porosity gradually increases as a distance from said first insulating film increases.
|