| 摘要 |
PURPOSE:To attain the efficient grade development of a dynamic type RAM, etc., by disconnecting selectively the prescribed fuse means of a common semiconductor substrate and setting the action mode of the dynamic type RAM. CONSTITUTION:The action mode of the dynamic type RAM, etc., is set by disconnecting selectively prescribed fuse means F1 and F2 and its bit constitution is set by changing a part of the photomask of the common semiconductor substrate. Consequently, by disconnecting selectively the prescribed fuse means F1 and F2 the switching of the action mode can be executed without changing the photomask and by changing a part of the photomask, the switching of the bit constitution can be realized without lowering the signal transmission characteristic of a circuit. Thus, without increasing in vain the number of the fuse means F1 and F2 and the photomasks and without lowering the action characteristic of an access time, the grade development of the dynamic type RAM, etc., can be efficiently realized. |
