MANUFACTURE OF SEMICONDUCTOR DEVICE

摘要

PURPOSE:To avoid failures such as a level discontinuity by stage of a wiring by a method wherein a compound film of a silicone oxide film and a phosphorous glass film is adopted as a layer insulating film, so that a smooth layer insulating film can be formed without deteriorating the reliability of insulation. CONSTITUTION:An Si oxide film 310 is formed on a surface of a MOS semiconductor device which is composed by forming a diffused layer 307 which is to be a source and drain and a gate electrode 309 on a surface of a semiconductor substrate 301 such as Si. Then a thin glass layer 311 with phosphorous density less than 11% is formed. The entire wafer is thermal processed, so that a difference in level is relieved by smoothening the phosphorous glass layer 311 like a slope 3110. A contact hole with a vertical wall is formed by hightly oriented dry etching with gas containing fluorine using a resist 312 as a mask. Then by wet-etching the surcumference of the contact hole is made smooth like dot line 903 because etching speed of the phosphorous glass layer is high.