Nand flash word line management using multiple fragment pools

Abstract

Systems and methods for improving NAND flash memory yields by identifying memory blocks with benign word line defects. Memory blocks including word line defects may be classified as incomplete memory blocks and may be used for storing data fragments. A data fragment may correspond with data written into memory cells associated with one or more contiguous word lines within a memory block that does not include a bad word line. In some cases, firmware associated with a NAND flash memory device may identify one or more data fragments based on the location of bad word lines within a memory block. A word line defect may be considered a benign defect if the defect does not prevent memory cells connected to other word lines within a memory block from being programmed and/or read reliably.