Flash memory device with automatic multi-page copyback function and block replacing method thereof

Block alternative to the flash memory device according to the present invention comprises the steps of storing page addresses is provided when the detected program / read and fail; Multi-step of generating a page copy-back the input of program information, an address for selecting each of the copy page of the memory block containing the said fail-page on the basis of the stored page address sequentially with; And a step of sequentially copying the data of the copy page of the memory block in response to the address generated by the sequence in the corresponding page of the empty memory blocks.