Patents by Inventor Akio Nakayama

Akio Nakayama has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5012309
    Abstract: A dynamic random access memory comprises a semiconductor substrate of a first conductivity type, a plurality of work lines, a plurality of bit lines, a plurality of active regions and a plurality of memory cells. The word lines extend in a first direction on a major surface of the semiconductor substrate. The bit lines are formed on the word lines and extend in a second direction intersecting with the first direction. The plurality of active regions are formed spaced apart at least at a predetermined interval in a third direction intersecting with the first and the second directions. Each of the active regions substantially forms a plane rectangle. The memory cells are arranged at intersection points of the word lines and the bit lines. Each memory cell comprises one and the other impurity regions of a second conductivity type, a gate electrode connected to the word lines, a storage node and a cell plate. The storage node is in contact with the other impurity region and is located above the bit line.
    Type: Grant
    Filed: April 20, 1990
    Date of Patent: April 30, 1991
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Akio Nakayama