摘要 |
When an isolating oxide is formed in a silicon substrate, a side wall is formed on the inner wall of a mask consisting of a lower silicon oxide layer and an upper silicon nitride layer for forming a groove in the silicon substrate in such a manner as to be laterally spaced from the inner wall of the upper silicon nitride layer, and the isolating oxide is formed from a silicon oxide layer deposited over the mask after removal of the side wall by using a polishing, thereby preventing the isolating oxide from undesirable side etching during an etching step for the lower silicon oxide layer.
|