| 摘要 |
PURPOSE:To reduce the surface area of a memory cell remarkably while increasing its capacity by jointly providing the inside of a groove formed in a substrate with a transistor and a capacitor. CONSTITUTION:First diffusion layers into which a reverse conductivity type impurity is diffused are formed to the surface of a semiconductor substrate 1 and the side walls of grooves 10, and function as reference potential electrodes 2 as drain electrodes. Gate oxide films 4 as first insulating films are shaped to the upper surface of the reference potential electrodes 2, and word lines 5 as gate electrodes consisting of a conductive substance 5 are formed to the upper surface of the oxide films 4. Second diffusion layers 3 having a conductivity type reverse to that of the semiconductor substrate 1 formed on the bases of the grooves 10 form source electrodes. One capacitor electrodes 7 composed of the conductive substance are shaped to the upper surfaces of the gate electrodes 5 through second insulating films 6. The nose surfaces of the capacitor electrodes 7 buried into the grooves 10 are connected electrically to the diffusion layers 3. The surfaces of the capacitor electrodes 7 are covered with thin third insulating films 8, and bit lines 9 as the other capacitor electrodes consisting of the conductive substance are buried the grooves 10. |
