| 摘要 |
PURPOSE:To increase an etching rate, and to maintain the uniformity of the distribution of the etching rate by specifying the ratio of a distance between a lower electrode and an upper electrode to the diameter of the upper electrode. CONSTITUTION:An upper electrode 2 and a lower electrode 3 are placed in parallel in a vacuum chamber 1 at the distance (d), a gas introducing port is formed to the upper section of the upper electrode 2, and a large number of gas outflow ports are formed to the surface opposite to the lower electrode 3. Exhaust ports are formed to the vaccuum chamber 1, and a semiconductor substrate 5 to be etched is placed on the lower electrode 3. An etching gas 4 is introduced from the upper section of the upper electrode 2, advances toward the semiconductor substrate 5 from a lower surface, and is discharged from the exhaust ports 6. When a high-frequency power supply 7 is connected to the lower section of the lower electrode 3, the upper electrode 2 is kept at ground potential and high-frequency power is applied, plasma is generated in the vacuum chamber 1, and the semiconductor substrate 5 is etched. When the diameter of the upper electrode 2 is made to be (g) and the distance between the upper electrode 2 and the lower electrode 3 (d) in such constitution, the uniformity of the etching rate is improved largely by bringing the ratio of g/d to 3.4 or less. |
