Patent ID: 9552251
Date: 2017-01-24
CPC Classifications: G06F,G11C,H01L

Claim:
1. A method for reading in a memory device, comprising: programming a first set of memory cells to a plurality of data states comprising lower data states and higher data states, wherein the first set of memory cells is connected to one word line layer in a set of word line layers in a memory structure; subsequently programming a second set of memory cells connected to another word line layer in the set of word line layers which is adjacent to the one word line layer, where each respective memory cell of the first set of memory cells is adjacent to, and is arranged along a common charge trapping layer with, a respective memory cell of the second set of memory cells; subsequently, in a first read operation, reading data from the first set of memory cells, the first read operation attempts to distinguish between the lower data states by biasing the one word line layer at a voltage for distinguishing between the lower data states while biasing the another word line layer with a pass voltage, and attempts to distinguish between the higher data states by biasing the one word line layer at a voltage for distinguishing between the higher data states while biasing the another word line layer with a pass voltage; determining that the data read in the first read operation comprises one or more uncorrectable errors; and in response to the determining that the data read in the first read operation comprises one or more uncorrectable errors, reading data from the first set of memory cells in a second read operation, the second read operation attempts to distinguish between the lower data states by biasing the one word line layer at a voltage for distinguishing between the lower data states while biasing the another word line layer with a pass voltage, and attempts to distinguish between the higher data states by biasing the one word line layer at a voltage for distinguishing between the higher data states while biasing the another word line layer with a pass voltage, wherein: