| 摘要 |
<p>PURPOSE:To enable to clarify the ion implanted region and to display the name and code of an ROM on a semiconductor device by employing the steps of thinly etching an insulating film in the photolithographic step of implanting ions to write the ROM and removing it. CONSTITUTION:A diffused layer 2 and an insulating film 3 are formed on a semiconductor substrate 1. A photoresist pattern 4 in which a region 9 for displaying an ion implanted gate region 6 and the name and code of an ROM is opened, as a mask ion implantation 5 is performed, the film 3 is thinly etched, and removed. A gate region 6' in which ion implantation 5 is not performed is not etched. The thicknesses and interference colors of the regions 6 and 6' are different, and stepwise difference is formed on the oxidized film. Accordingly, the ion implanted region can be clearly identified on the pattern, and the name and code of the ROM can be simultaneously recorded on a semiconductor device.</p> |
