| 摘要 |
PURPOSE:To improve the reliability of an element by using an erasable and programmable ROM cell for selecting a redundancy circuit. CONSTITUTION:A field oxide film 2, a gate oxide film 3 and a floating gate 4 are formed to the surface of a p type silicon substrate 1, and a control gate 6 is formed on the gate 4 through a gate oxide film 5. An n<+> type impurity region 7 connected to a main circuit and an n<+> type impurity region 8 connected to a redundancy circuit are shaped to the surface of an element region on both sides of the gate 6. When the main circuit is defective, electrons are injected to the gate 4 and writing is executed, and a transistor is turned OFF and the defective main circuit is released. |
