| 摘要 |
PURPOSE:To enable the reactive ion etching device which generates no residue and shapes a pattern having high accuracy by forming an opening section by a concave section or a through port to an electrode at the ground side, giving plasma discharge a hollow effect and improving the degree of dissociation. CONSTITUTION:A cathode 2 is fitted to a reaction vessel 1 grounded, and a high-frequency power supply 3 in 13.56MHz is connected through a matching circuit 4. An anode 5 oppositely forming parallel plate electrodes is grounded, and a workpiece 7 is placed onto a carbon board 6 on the surface of the cathode 2. The cathode 2 or the anode 5 is turned during etching in order to obtain the uniformity of a wafer. The anode 5 has a 50cm diameter, and the concave section 5' having a 6mm. diameter and 12mm. depth is shaped at the center. When the total flow rates of CF3Br and Cl2 are made 30SOCM and a phosphorus doped poly-Si film formed onto the silicon wafer 20 in the figure a through CVD through a thermal silicon oxide film 21 under the states of a 60% Cl2 flow rate ratio, 0.1 Torr total pressure and 0.3w/cm<3> high-frequency power is etched while using a photo-resist as a mask, an etching profile in which there is no residue and undercut in the figure b is obtained. |
