| 摘要 |
PURPOSE:To simplify the steps of forming a mask in a manufacturing method of a semiconductor device having a ROM by forming an impurity implanting mask for rewriting information in the same steps as the steps of forming a data line or a ground line. CONSTITUTION:After field insulating films 2, 3 conductive layers 4A, 4B and an insulating film 5 are formed on the main surface of a semiconductor substrate 1, a semiconductor region 6 is formed by ion implanting, thereby forming an MISFETQ1 having the first threshold value. Then, after an insulating film 7 for coating a semiconductor element is formed, the films 3, 7 on the region 6 are removed to form a connecting hole 8. Then, a conductive layer 9A to become a data line LD and a ground line GL and a mask 9B for implanting an impurity for rewriting information are formed in the same steps on the film 7 for connecting the region 6. Then, the mask 9B is used to form an MISFETQ2 having the second threshold value. |
