US Patent 9000409 3D semiconductor memory device and manufacturing method thereof

The present application discloses a 3D semiconductor memory device having 1T1R memory configuration based on a vertical-type gate-around transistor, and a manufacturing method thereof. A on/off current ratio can be well controlled by changing a width and a length of a channel of the gate-around transistor, so as to facilitate multi-state operation of the 1T1R memory cell. Moreover, the vertical transistor has a smaller layout size than a horizontal transistor, so as to reduce the layout size effectively. Thus, the 3D semiconductor memory device can be integrated into an array with a high density.