| 摘要 |
<P>PROBLEM TO BE SOLVED: To change the shape of deep holes formed in a bowing shape to a straight shape. <P>SOLUTION: A laminate structure including a first silicon oxide film 5 of impurity-doped and a second silicon oxide film 6 of impurity non-doped is formed on a silicon nitride film 4. Next, first holes 8 with a bowing shape are formed in the laminate structure by dry etching. Subsequently, the silicon nitride film 4 and the first silicon oxide film 5 are retracted by wet etching using thermal phosphoric acid to form second holes 9 in which the bottom of the bowing portion is widened. <P>COPYRIGHT: (C)2012,JPO&INPIT |
