| 摘要 |
PROBLEM TO BE SOLVED: To provide an apparatus and a method for protecting a charge storage element against photocurrent in a silicon integrated circuit. SOLUTION: In order to protect against photocurrents generated by a storage node circuit 154, an n-type well guard ring 164 is disposed at a place as near as to a transistor or another element in the node circuit 154. As a result, a silicon region exposed which is capable of generating a current in a region adjacent to the node circuit becomes a minimum, and the guard ring 164 captures the photocurrent generated outside of the node circuit 154. In order to protect against the photocurrents generated in the node circuit 154, an aluminum interconnecting layer 158 is disposed on the node circuit 154 separated by an insulating layer 156 of a silicon dioxide. This forms a shield with respect to light and protects the circuit 154 by having the light undergo reflection. |
