Patent ID: 9711563
Date: 2017-07-18
CPC Classifications: H01L

Claim:
1. A method of manufacturing a semiconductor device, comprising: forming, over a semiconductor substrate comprising a first region and a second region, a first film having a first part located over the first region and a second part located over the second region; reducing a thickness of a portion of the first film located over the first region, so that an upper face of the first part is positioned at a lower height from the semiconductor substrate than an upper face of the second part, and so that a first difference in height from the semiconductor substrate between the upper face of the first part and the upper face of the second part is larger than a second difference in height from the semiconductor substrate between a lower face of the first part and a lower face of the second part; after forming the first film, forming one or more trenches in the first region penetrating the first part of the first film and reaching an inside of the substrate and one or more trenches in the second region penetrating the second part of the first film and reaching the inside of the substrate; forming, over the first film, a second film which is an insulating film, a portion of the second film passing through the one or more holes of the first part and being located inside the one or more trenches of the first region, and a portion of the second film being located inside the one or more trenches of the second region; and polishing the second film to remove a portion of the second film located over the first film, so that a third difference in height from the semiconductor substrate between the upper face of the first part and the upper face of the second part after the polishing is smaller than the first difference, wherein in the forming of the second film, the second film is formed so that the second film has a first portion located over the first region and a second portion located over the second region and an upper face of the first portion of the second film is positioned at a lower height from the semiconductor substrate than an upper face of the second portion of the second film.