| 摘要 |
PROBLEM TO BE SOLVED: To provide an NOR-type mask ROM and its manufacturing method of, whereby in programming ROM codes uniformity of an impurity ion implanted in channel regions can be sufficiently improved to suppress programming defects. SOLUTION: After forming a buried diffused layer 102 as sources/drains of cell transistors on a semiconductor substrate 100, a gate dielectric film 103 and gate pattern 104 are formed. After laminating layer insulation films 106, 108 thereon, contact holes are bored, and a metal pattern 110 connected to drain regions are formed. An insulation film 116 filling space between metal patterns to flatten its top surface, and a step is executed such that a passivation layer 112 is laminated thereon and selectively etched to expose bonding pads. By having ion implantation in a substrate having the passivation layer 112, an ROM code programming step is conducted. |
