| 摘要 |
<p>The etch rate of silicon dioxide, particularly thermally grown silicon dioxide, in boiling phosphoric acid, can be controlled by deliberately adding additional silicate to the acid. For thermally grown silicon dioxide, the etch rate can be reduced from about 5.ANG. per minute with no added silicate, to about 0.5.ANG./minute with 1 gram of added silicate to about 1 litre of acid. - i</p> |
