Spherical Shallow Trench Isolation with silicon nitride layer in Buried Gate DRAM for reducing pass gate disturbance

In this paper, we propose a solution that involves adding a silicon nitride (Si
3
N
4
) layer to the spherical shallow trench isolation (STI) structure. By optimizing the spherical STI structure and adding the Si
3
N
4
layer. The addition of Si
3
N
4
is shown to cause a decrease in pass gate effect (PGE) based on the measurement results. The proposed structure reduced the PGE compared to the currently used BCAT structure.