Semiconductor memory device and method of forming the same

Abstract

The invention discloses a semiconductor memory device and its forming method. The semiconductor memory device includes a substrate, multiple gates, multiple bit lines and dummy bit lines. A plurality of gates are arranged inside the substrate along the first direction, a plurality of bit lines are arranged on the substrate along the second direction, dummy bit lines are arranged outside the plurality of bit lines along the second direction, and the dummy bit lines are arranged outside the plurality of bit lines along the second direction. A plurality of protrusions are provided on the side wall, the plurality of protrusions extend from the top surface to the bottom surface of the plurality of bit lines, and the plurality of protrusions have the same length in the second direction. In this way, the gates extending beyond the bit lines can be isolated by using the protrusions, and a semiconductor memory device with better component reliability can be formed under a simplified manufacturing process.

Description

technical field [0001] The present invention relates to a semiconductor device and its forming method, in particular to a semiconductor storage device and its forming method. Background technique [0002] With the trend of miniaturization of various electronic products, the design of dynamic random access memory (DRAM) units must also meet the requirements of high integration and high density. For a DRAM cell with a recessed gate structure, because it can obtain a longer carrier channel length in the same semiconductor substrate to reduce the leakage of the capacitor structure, it is under the current mainstream development trend , which has gradually replaced DRAM cells with only planar gate structures. [0003] Generally, a DRAM cell with a recessed gate structure includes a transistor device and a charge storage device to receive voltage signals from bit lines and word lines. However, due to the limitation of process technology, the existing DRAM cells with recessed gat...

AI Technical Summary

Problems solved by technology

However, limited by the process technology, there are still many defects in the existing DRAM cells with recessed gate structures, which need to be further improved to effectively improve the performance and reliability of related memory components

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