Memory system and read reclaim method thereof

A memory system comprising:

• a nonvolatile memory device including:
• a first group of flash memory cells formed of a plurality of first memory blocks, each of the first group of flash memory cells being configured to store 1-bit data per cell;
• and
• a second group of flash memory cells formed of a plurality of second memory blocks, each of the second group of flash memory cells being configured to store 3-bits data per cell;
• and
• a memory controller configured to control the nonvolatile memory device,
• wherein the memory controller is configured to perform a read reclaim operation to transfer valid data stored in one of the plurality of second memory blocks to one or more memory blocks of the plurality of first memory blocks,
• the read reclaim operation is performed on a first portion of the valid data at a first time, and is performed on a second portion of the valid data at a second time that is different from the first time, and
• the memory controller is configured to perform one or more program operations to transfer a third portion of the valid data that is read from the one or more memory blocks of the plurality of first memory blocks to another of the plurality of second memory blocks other than the one of the plurality of second memory blocks.

A method of operating a nonvolatile memory system including a controller and a nonvolatile memory device, the nonvolatile memory device including a plurality of first memory cells and a plurality of second memory cells, each of the plurality of first memory cells being configured to store 3-bit data, each of the plurality of second memory cells being configured to store 1-bit data, the method comprising:

• reading, at a first voltage level, first data from a first portion of the plurality of first memory cells;
• performing an error checking and correction (ECC) operation on the first data to generate ECC-performed first data;
• reading, at a second voltage level, second data that is read from the first portion of the plurality of first memory cells when a number of error bits of the ECC-performed first data exceeds a threshold correctable by the ECC operation;
• performing the ECC operation on the second data to generate ECC-performed second data;
• outputting to the nonvolatile memory device first page data that includes either the ECC-performed first data or the ECC-performed second data;
• programming the first page data in a first portion of the plurality of second memory cells;
• reading the programmed first page data in the first portion of the plurality of second memory cells at a first time;
• programming in a second portion of the plurality of first memory cells the programmed first page data that is read at the first time;
• reading the programmed first page data in the first portion of the plurality of second memory cells at a second time;
• and
• re-programming in the second portion of the plurality of first memory cells the programmed first page data that is read at the second time.

A memory system comprising:

• a nonvolatile memory device including a plurality of first memory cells and a plurality of second memory cells, each of the plurality of first memory cells being configured to store 3-bit data, each of the plurality of second memory cells being configured to store 1-bit data, the nonvolatile memory device including a memory cell array having a vertical or stack-type three-dimensional array structure;
• and
• a controller configured to control the nonvolatile memory device to perform a read operation, a program operation and a re-program operation,
• wherein the controller is configured to perform an error checking and correction (ECC) operation on first data to generate ECC-performed first data, the first data being read from a first portion of the plurality of first memory cells at a first voltage level,
• the controller is configured to perform a read retry operation and the ECC operation on second data to generate ECC-performed second data when a number of error bits of the ECC-performed first data exceeds a threshold correctable by the ECC operation, the read retry operation including reading the second data stored in the first portion of the plurality of first memory cells at a second voltage level that is different from the first voltage level, the second data being read from the first portion of the plurality of first memory cells,
• the controller is configured to output to the nonvolatile memory device first page data including either the ECC-performed first data or the ECC-performed second data,
• the nonvolatile memory device is configured to program the first page data in a first portion of the plurality of second memory cells,
• the nonvolatile memory device is configured to read the programmed first page data in the first portion of the plurality of second memory cells,
• the nonvolatile memory device is configured to program in a second portion of the plurality of first memory cells the programmed first page data that is read at a first time from the first portion of the plurality of second memory cells,
• the nonvolatile memory device is configured to re-program in the second portion of the plurality of first memory cells the programmed first page data that is read at a second time from the first portion of the plurality of second memory cells,
• wherein the first time is different from the second time.