| 摘要 |
PURPOSE: A method for forming a wine glass type contact hole is to provide a good profile and step coverage, and to reduce cleaning time, by use of a dry-etching process, thereby simplifying the manufacturing process and increasing productivity, and advantageously securing step coverage. CONSTITUTION: A photoresist pattern for forming a contact hole is formed on a semiconductor substrate(11) on which an interlayer dielectric oxide layer(12) is formed. A portion of the exposed oxide layer is isotropically dry-etched using SF6 gas such that an aspect ratio is to 0.5 to 1:1 under the condition of 200 to 1000 mT of pressure and 100 to 3000 W of RF electric power. The oxide layer is anisotropically etched by use of the photoresist pattern as an etching mask. The anisotropic-etching is carried out in condition of 100 to 3000 W of RF electric power and using fluorocarbon based gas as an etching source gas. The photoresist pattern is then removed by use of O2 plasma or N2H2 plasma.
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