FERROELECTRIC RANDOM ACCESS MEMORY DEVICE

摘要

A ferroelectric RAM device is provided to increase an effective channel length by forming an improved dual gate cell structure by using upper and lower gates formed in a groove of a semiconductor substrate. A groove is formed within a gate forming region of a semiconductor substrate(SUB). A first gate electrode(GM1) is formed along an inner surface of the groove. A first gate insulating layer(OX1) is formed on the first gate electrode. A channel layer(CH) is formed along an upper surface of the resultant structure. A second gate insulating layer(OX2) is formed on the channel layer of the groove portion. A ferroelectric film(FL) is formed on the second gate insulating layer. A second gate electrode(GM2) is formed on the ferroelectric film.