Patent ID: 7084508

Claim:
A semiconductor device comprising: a semiconductor base layer; a plurality of conductive elements formed on said semiconductor base layer, a silicon dioxide film covering a side surface and a top surface of said plurality of conductive elements, said silicon dioxide film reaching to said semiconductor base layer; an etching resistant film covering said silicon dioxide film on at least the top surface of said silicon dioxide film; an interlayer insulating film, of material different from the etching resistant film material, formed on said etching resistant film so as to cover said etching resistant film, the interlayer insulating film comprising a lower interlayer and an upper interlayer, the lower interlayer having a higher etching rate than that of the upper interlayer; and a contact hole formed through the interlayer insulating film and extending between adjacent conductive elements to the semiconductor base layer, the hole being longer through the upper interlayer than the lower interlayer; wherein the lower interlayer insulating film is in direct contact with the etching resistant film, the upper interlayer insulating film is in direct contact with the lower interlayer insulating film; the plurality of conductive elements are separated from the hole by the silicon dioxide film; and the diameter of said contact hole is larger between said adjacent conductive elements than the diameter of the contact hole between the upper and lower interlayer insulating films.