| 摘要 |
PURPOSE:To round the edge section of a via hole, to remove a disconnection at the step of a wiring and to obtain a contact hole for a multilayer interconnection having excellent coatability at the step and high reliability by using a plasma Si3N4 film formed at room temperature as a hard mask material and adding heat treatment after the patterning of a hard mask. CONSTITUTION:A conductor 12 is patterned on a lower base 11, an insulating film 13 consisting of an organic resin film is shaped onto the conductor 12, and a hard mask 14 composed of an Si3N4 film formed at room temperature is shaped onto the insulating film 13. A resist pattern 15 is formed onto the hard mask 14 and the hard mask 14 is patterned, and the hard mask 14 and the insulating film 13 are thermally treated. Dry etching is conducted in an isotropic manner through reactive ion etching in an O2 gas atmosphere. The hard mask 14 is removed through a method such as a dry etching method, and a contact hole for a multilayer interconnection is formed. Second layer aluminum 17 is deposited in the contact hole. Accordingly, a via hole, an edge section thereof is rounded, can be formed. |
