| 摘要 |
<p>A semiconductor device comprising a main circuit, redundant circuit, and their switching circuit, wherein switching is executed by changing the resistance of part of the switching circuit by light without fusing wire layers. A resistor layer (14) made of polycrystalline silicon doped with an impurity such as phosphorus is connected with two aluminum wires (19, 19) through contact holes (18, 18). Other wire layers formed in the same process as the resistor layer (14) in the switching circuit are formed to have low resistance because they are annealed in the semiconductor device fabrication process. However, only the resistor layer (14) maintains a high resistance because it is not annealed. When a defective element in the main circuit is changed to a non-defective element in the redundant circuit, the resistance layer (14) is locally annealed to activate the impurity in it so that its resistance decreases.</p> |
