| 摘要 |
PROBLEM TO BE SOLVED: To make capacitance and capacitance variances less than those of a conventional air gap structure. SOLUTION: Wiring 26 containing copper as a principal component is formed on an insulating film 17 on a substrate. Then insulating films 21 and 22 for a reserver pattern and a barrier insulating film 29 are formed, and an insulating film 31 having a function of suppressing or preventing diffusion of copper is formed on an upper surface and a side surface of the wiring 26 and on the insulating film 17 and insulating film 29. At this time, the film thickness of the insulating film 17 in a narrow inter-wiring space bottom part is made less than the film thickness of the insulating film 31 on the wiring 26 to efficiently reduce the wiring capacitance of a thin line pitch. Then an insulating film 36 and an insulating film 37 are formed which have low dielectric constant. At this time, the insulating film 36 is formed between adjacent wiring lines of the wiring 26 so as to have a higher deposition speed above opposite wiring side surfaces than below them, thereby forming an air gap. Lastly, the insulating film 37 is flattened by inter-layer CMP. COPYRIGHT: (C)2010,JPO&INPIT |
