| 摘要 |
PURPOSE:To improve dimensional accuracy by interrupting etching once at a step before the completion of etching, reinforcing a section in the vicinity of a boundary between a mask material and a film to be processed by a second mask material and reopening etching. CONSTITUTION:Etching is interrupted once at a step before the completion of etching such as one before an oxide film 2 disappears, and a second mask material 5 is shaped on the surface of a semiconductor substrate 1. When the mask material 5 is baked and treated and removed, the second mask material 5 filled into a clearance between a first mask material 3 and the oxide film 2 is difficult to be removed, and the clearance is not exposed and remains because it is covered with the mask material 3 particularly on a positive type resist. Etching is reopened under the state in which one part of the second mask material 5' remains, and the oxide film 2 is etched completely to a desired pattern. Accordingly, since a section in the vicinity of a boundary between the photo-resist 3 and the oxide film 2 is protected by the second mask material 5, etching in the lateral direction is inhibited, thus enabling etching processing with high dimensional accuracy. |
