Semiconductor device and method of manufacture thereof

A method for manufacturing a semiconductor device, comprising the steps of:

• forming a plurality of gate electrodes on a semiconductor substrate;
• forming a hygroscopic insulating film covering the plurality of the gate electrodes;
• forming a first low-hygroscopic insulating film on the hygroscopic insulating film;
• exposing the hygroscopic insulating film to an upper surface above the semiconductor substrate positioned between the gate electrodes adjacent to each other among the plurality of the gate electrodes and reducing a film thickness of the exposed hygroscopic insulating film by planarizing a surface of a laminated film consisting of the hygroscopic insulating film and the first low-hygroscopic insulating film;
• forming a second low-hygroscopic insulating film on the hygroscopic insulating film with the reduced film thickness at a time of the planarizing above the semiconductor substrate positioned between the gate electrodes adjacent to each other;
• forming a through-hole passing through the second low-hygroscopic insulating film and the hygroscopic insulating film with the reduced film thickness at the time of the planarizing;
• and
• filling the through-hole with a conductor.