| 摘要 |
PROBLEM TO BE SOLVED: To avoid the deterioration of the aspect ratio of contacts, which makes trouble in a microscopic processing of a semiconductor device, and the expansion of a margin for the countermeasure against the deterioration. SOLUTION: The upper edges 405a of buried contacts 405 are extended into a tapered shape and have a margin to a positional shift of the buried contacts 409 in an upper shift. The contacts 409 are provided at positions directly over the buried contacts 405 in a lower layer and the upper edges 409a of the contacts 409 are widely opened and are formed into a tapered shape like the buried contacts 405 in the lower layer. Thereby, the contacts are made self- aligned with gate electrodes. |
