Kabushiki Kaisha Toshiba

Hiromasa Fujimoto

Keisuke Yonehama

Eiji Sakagami

Naoki Koido

A memory cell array of a NOR type flash memory is constructed by arranging memory cell transistors in a matrix, each of the memory cell transistors includes a contact connecting a semiconductor substrate to an overlayer wire. Columns of the memory cell transistors are isolated from one another by shallow trench isolations. The height of top surface of a filling oxide film in the shallow trench isolation which is adjacent to each drain contact is equal to that of top surface of the drain region. The top surface of a filling oxide film in the shallow trench isolation which is adjacent to each channel region is higher than a top surface of the semiconductor substrate in the channel region.

Nonvolatile semiconductor memory device and method for manufacturing the same

A semiconductor memory device, including a first memory cell having a first gate electrode, a first diffusion layer, and a second diffusion layer; a first contact layer connected to the first diffusion layer of the first memory cell; a second contact layer connected to the first contact layer; a second memory cell having a second gate electrode, a third diffusion layer and a fourth diffusion layer, the second gate electrode of the second memory cell electrically connected to the first gate electrode of the first memory cell, the first and second memory cells arranged in a direction perpendicular to the first bit line; and a conductive layer commonly connected to the second diffusion layer of the first memory cell and the fourth diffusion layer of the second memory cell, a height of the conductive layer substantially being coplanar with a height of the first contact layer.

Growing community of inventors

Yokkaichi, Japan

Hiromasa Fujimoto