Heavy Ion and Proton-Induced Single Event Upset Characteristics of a 3-D NAND Flash Memory

We evaluated the effects of heavy ion and proton irradiation for a 3-D NAND flash. The 3-D NAND showed similar single-event upset (SEU) sensitivity to a planar NAND of identical density in the multiple-level cell (MLC) storage mode. The 3-D NAND showed significantly reduced SEU susceptibility in single-level-cell storage mode. In addition, the 3-D NAND showed less multiple-bit upset susceptibility than the planar NAND, with fewer number of upset bits per byte and smaller cross sections overall. However, the 3-D architecture exhibited angular sensitivities for both base and face angles, reflecting the anisotropic nature of the SEU vulnerability in space. Furthermore, the SEU cross section decreased with increasing fluence for both the 3-D NAND and the Micron 16-nm planar NAND, which suggests that typical heavy ion test fluences will underestimate the upset rate during a space mission. These unique characteristics introduce complexity to traditional ground irradiation test procedures.