| 摘要 |
PURPOSE:To obtain the oxidized film having a flat surface by preparing an etching groove vertical to an Si substrate, together with an Si3N4 film, by using a resist mask provided adjacently with small holes or narrow grooves, and by subjecting the same to thermal oxidation. CONSTITUTION:The thin Si3N4 film 2 is provided on the Si substrate 1 and the resist mask 3 is applied thereto. Resist width Wp is slightly larger than groove width Ws. Next, when Si3N4 and Si are etched through reactive spatter etching, lateral etching is not caused, while the groove sufficiently deep compared with the width Ws is formed vertically. When the resist is removed and the thermal oxidation is applied, SiO2 grows from both sides of the groove 4 and fills up the groove. Si3N4 being removed finally, an SiO2 layer having the flat surface is obtained. By this method, the thick oxidized film can be obtained in a short time and further a highly-precise insulation-substance layer having the flat surface and being fitted for minute elements can be obtained. |
