| 摘要 |
PURPOSE:To provide a semiconductor device, which suppresses the lattice defects in a board by lessening the cells implanted into ROM, and a write-in method by which the write in of data is easy. CONSTITUTION:A mask ROM, which outputs data of either '1' or '0', is equipped with an output control means which decides whether to output data after inverting them or output them as they are, according to the data that a cell array 10 has. In case of using user data which abound with '1' or '0' data being decided by performing implantation into ROM, the data inversion is performed by an output control means, and in the case of using user data which abounds with data being made without performing implantation into ROM, the data inversion is not performed. The memory cells in a cell array being implanted into ROM regardless of the content of the user data by an output means are lessened. The ion implantation into a MOS transistor, which breaks the path of the output control means, is performed at the same time with the ROM implantation into a memory cell. |
