| 摘要 |
<p>PURPOSE:To obtain the ROM on which desired information is written in by a method wherein a leak current is increased by selectively introducing a metal atom at a part of the storage section of a desired memory cell, and other memories are remained in the state of conventional form. CONSTITUTION:A gate insulating film 2, a gate electrode 3, a dielectric film 6 and a capacity electrode 7 are formed respectively. After P-ion has been implanted in a source region 4 and a drain region 15 using a self-matching method, Fe is implanted into the depletion layer of the junction part, rather than the drain region 15, using an ion beam of 1mum or thereabout in diameter, thereby enabling to contain a large quantity of metal therein. As a result, the junction having an increased leak current is obtained, an electric charge is leaked out and the accumulation thereof on a capacitor can be prevented. The desired memory is selectively formed into the structure as above, the memory is corresponded to information ''0'', for example, and ROM is obtained corresponding to ''1'' with the other memory cells in the conventional structure. According to this constitution, RAM and ROM can be selected while the memory device is being manufactured, thereby enabling to perform works in high efficiency.</p> |
