Short circuit reduction in a ferroelectric memory cell comprising a stack of layers arranged on a flexible substrate

摘要

A ferroelectric memory cell (1) and a memory device (100) comprising one or more such cells (1). The ferroelectric memory cell comprises a stack (4) of layers arranged on a flexible substrate (3). Said stack comprises an electrically active part (4a) and a protective layer (11) for protecting the electrically active part against scratches and abrasion. Said electrically active part comprises a bottom electrode layer (5) and a top electrode layer (9) and at least one ferroelectric memory material layer (7) between said electrodes. The stack further comprises a buffer layer (13) arranged between the top electrode layer (9) and the protective layer (11). The buffer layer (13) is adapted for at least partially absorbing a lateral dimensional change (ΔL) occurring in the protective layer (11) and thus preventing said dimensional change (ΔL) from being transferred to the electrically active part (4a), thereby reducing the risk of short circuit to occur between the electrodes.

主权项

1. A ferroelectric memory cell comprising a stack of layers arranged on a flexible substrate, wherein said stack comprises an electrically active part and a protective layer for protecting the electrically active part against scratches and abrasion, wherein said electrically active part comprises a bottom electrode layer and a top electrode layer and at least one ferroelectric memory material layer between said electrodes, wherein the stack further comprises a buffer layer, arranged between the top electrode layer and the protective layer, the buffer layer being adapted for at least partially absorbing a lateral dimensional change occurring in the protective layer and thus preventing said dimensional change from being transferred to the electrically active part, wherein the buffer layer is adapted for at least partially absorbing the lateral dimensional change by being of a coherent material and having such layer thickness that a lateral dimensional deformation in a top portion of the buffer layer facing the protective layer results in substantially less lateral dimensional deformation in a bottom portion facing the electrically active part, when said lateral dimensional deformation in the upper part is caused by the lateral dimensional change of the protective layer, the difference in lateral deformation between the top and bottom portions corresponding to absorbed lateral dimensional change.