| 摘要 |
PURPOSE:To obtain flat multilayer interconnections by etching a metal film with an etchant for forming an inactive state while rubbing the surface of the metal film, thereby removing the metal of an unnecessary region. CONSTITUTION:A diffused region 102 is formed on a silicon substrate 101, a contacting hole is opened at a silicon oxide film 103, and a silicon nitride film 104 is coated as the first layer interconnecting insulating film. After the film 104 of the region for forming the interconnection is removed, an aluminum film 105 for interconnection is coated. Then, the film 105 is etched with a buffer HF solution while rubbing the surface of the film 105. The film 105 is removed on the film 104 by etching by utilizing the inactive state formed at this time, the film 105 of the interconnection region remains to be buried in the film 104. Thereafter, after a silicon oxide film 103 is coated as 1-2 layer insulating film, a through-hole is formed. The second and the following interconnections can be similarly formed. Thus, since the interconnection are formed by selectively removing only by rubbing the metal of the unnecessary region, flat multilayer interconnections can be readily formed. |
