Granular electron injection and random telegraph noise impact on the programming accuracy of NOR Flash memories

Abstract

This work investigates for the first time chargegranularity effects during channel hot-electron programming of NOR Flash memories, comparing the granular electron injection and the random telegraph noise limitations to the accuracy of the programming algorithm. The spread of the threshold voltage shift that is determined by the electron injection statistics is studied as a function of the channel hot-electron programming conditions, explaining the results by an analytical model accounting for the sub-poissonian nature of the electron transfer to the floating gate. The scaling trend of the injection statistical spread is then investigated on NOR technologies ranging from ½ ¼ to nm and its contribution to the width of the threshold voltage distribution in presence of a program verify level is separated from that given by random telegraph noise.

Reliability of NAND Flash Memories: Planar Cells and Emerging Issues in 3D Devices

“…A comparative analysis of the impact of charge detrapping on the width of the V T distribution after cycling and bake was reported in [239] and shown in Figure 28, normalized to the ISPP step V s . The two bottom-most contributions are related to the time-0 placement of the V T distribution-namely, the ISPP step V s and the fluctuation in the number of injected electrons per step [158,159,240]-and are not discussed here. The remaining part is made up of a native RTN contribution plus the additional terms induced by cycling.…”

Defect properties of high-k/metal-gate metal–oxide–semiconductor field-effect transistors determined by characterization of random telegraph noise

“…RTN has therefore been the focus of great interest over the last decade. 6,7) It is well known that RTN has severe impact on static random access memory (SRAM), 8) dynamic random access memory (DRAM), 9) NOR flash memory, 10) NAND flash memory, 11,12) and CMOS image sensors. 13) In the RTN process, defects affect the driving force of electron transfer kinetics.…”