| 摘要 |
PURPOSE:To facilitate the formation of a groove on a substrate by alternately repeating the step of selectively etching the substrate by a dry etching method using a gas plasma and the step of forming a film on the surface to be etched with the plasma. CONSTITUTION:A silicon oxide film 2 is formed on a substrate 1, and etched with a patterned resist 3 as a mask. With the film 2 as a mask the substrate 1 is etched by a reactive ion etching method (by employing Cl2 for reactive gas). When the etching is stopped, the reaction gas is instead substituted for O2 and treated in a plasma atomosphere, a thin oxide film 5 is formed on the inner surface of a groove 4. When the reaction gas is again substituted for Cl2 in this state, the bottom of the groove 4 is progressively etched by ion implantation in a plasma to form a deep groove 4'. Thus, an ultrafine deep perpendicular groove is formed. |
