| 摘要 |
<p>PURPOSE:To provide the substrate capable of forming an anodically oxidized film of Ta with which a selection ratio to Ta as the essential component of metallic wirings is obtainable in dry etching and leakage hardly arises by using a nitrogen compd. of Al for a substrate protective film. CONSTITUTION:The substrate protective film 5 consisting of AlNx is formed on the front surface on an insulating base substrate 1 consisting of glass, etc., and a Ta metallic film is formed by a sputtering method over the entire surface of the substrate protective film 5. This Ta metallic layer is dry etched by an etching gas consisting of a gaseous mixture composed of CF4 and O2 or SF4 and O2 to form patterns of gate electrode wirings 2. The front surfaces of the gate electrode wirings 2 are thereafter anodically oxidized, by which the anodically oxidized films 6 consisting of Ta2O5 are formed. The substrate protective film 5 consisting of the AlNx protects the base substrate 1 against the etching gas of the Ta metallic layer. As a result, the sufficient selection rate with the Ta is obtd. in the dry etching stage and the increase of the level difference from the gate electrode wirings 2 does not arise.</p> |
