Threshold Voltage Variations of 3D V-NAND Flash Memory Devices Due to Different Positions and Angles of the Single Grain Boundary

Abstract

The threshold voltage (Vth) variations of 3D V-NAND flash memory devices due to different positions and angles of the single grain boundary (SGB) were simulated by using the computer-aided design simulation tool Sentaurus. The SGB increased the Vth value and decreased the saturation drain current. The SGB was placed at various positions and angles in the channel to analyze the effects of the SGB on a macaroni-type poly-silicon channel. The Vth value was significantly affected by the change in the peak value of the conduction band energy when the position of the SGB was changed. Furthermore, the dependency of the Vth values on angles at various positions was investigated.