| 摘要 |
PURPOSE:To accurately obtain a less-than-1mum minimal resist pattern by shifting the same pattern on a semiconductor wafer and exposing more than two times through the reduced projection type exposure method used mainly for loose devices of 2-3mum. CONSTITUTION:A positive photo resist 2 with a thickness of approx. 1mum is formed on a substrate 1, and a specified pattern is transferred to this resist using a reduced projection type exposure apparatus. Portions d of the resist 2 shown in the figure are the ultimately desired portions, while portions 3 are alkali-solubilized portions resulted from the first pattern transfer. Without removing the substrate 1 from the exposure apparatus after the first pattern transfer, an exposure position is shifted a specified length of less than 1mum and the same pattern is again transferred so that alkali-solubilized portions 4 are partially produced within the portions 3. Finally, the substrate is removed from the apparatus and subjected to development to remove the portions 3, 4 to retain the desired portions d on the substrate 1. |
