JPS57138162A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To lessen the crystal distortion as well as to increase the yield rate of elements for the subject semiconductor device by a method wherein, when the element region provided on a semiconductor substrate is insulation-isolated using an insulating film wherein a groove is buried, a thin SiO2 film, whereon the groove is not buried, is formed on the surface of the substrate immediately after the formation of the groove using an Si3N4 film as a mask, then the SiO2 film is removed, and the desired insulating film is provided. CONSTITUTION:An N type layer 101 is epitaxially grown on a P type Si substrate 107, the laminated film of the SiO2 film 102 and the Si3N4 film 103 is covered on the N type layer 101, and a groove 105 entering into the layer 101 is formed by performing a plasma etching and a wet etching successively using the resist film 104, having the aperture corresponding to the groove to be formed, as a mask. Then, the film 104 is removed, a thermal oxidation is per formed using the film 103 as a mask, an SiO2 film 108 to be coupled to the film 102 is generated along the exposed surface of the groove 105, the film 108 is removed using buffered hydrofluoric acid and the edge 109 of the exposed groove 105 is roundishly shaped up. Subsequently, the groove 105 is buried with an SiO2 film 106 by performing a selective oxidation using the commonly used method.