Heavy Ion-Induced SEUs and Layer Dependence in Dual-Deck 3-D NAND Flash Memories

The 3-D <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">nand</small> technology has garnered increasing attention within space applications as a focal point of commercial competition and industrial evolution in semiconductor memory. With the increase in the number of layers, dual-deck architecture is being gradually integrated into products to reduce process fluctuations and improve electrical performance. However, it is essential to carefully evaluate the response of such new devices to radiation effects. In this study, the 3-D distribution characteristics of single-event upsets (SEUs) were investigated in 128-layer dual-deck 3-D <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">nand</small> flash memory induced by heavy ion irradiation. By measuring the threshold voltage distribution of charge-trapping (CT) cells under different heavy ion conditions, the dependence of the number and size of multiple cell upsets (MCUs) on the linear energy transfer (LET) was analyzed, and the underlying physical mechanisms of these radiation effects were explored. In addition, the variation of SEU along the layer is closely related to the dual-deck structure and channel hole etch process. This work provides important reference data for improving the reliability design of 3-D <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">nand</small> flash devices in radiation environments.