A nonvolatile semiconductor memory device comprising a main memory cell array and a spare memory cell array, capable of freely accessing data in the spare memory cell array irrespective of the physical addresses of the spare memory cell array, and a method thereof are disclosed. The logical addresses of the spare memory cell array are assigned prior to the logical addresses of the main memory cell array in response to a first control signal, and data stored in the spare memory cell array is read earlier than data in the main memory cell array.
Method of programming nonvolatile memory devices are provided in which data is programmed into a first plurality of memory cells of the nonvolatile memory device. At the same time associated programming confirmation information is programmed into at least one second memory cell of the nonvolatile memory device. Then, a determination is made as to whether the data was correctly programmed into the first plurality of memory cells based on an evaluation of (1) the threshold voltage distributions of at least some of the first plurality of memory cells and (2) the threshold voltage distribution of the at least one second memory cell. Methods of resuming a data programming operation after an interruption such as a loss of power are also provided.
