Non-volatile semiconductor memory device with writing sequence enabling early-stage judgement of writing

A non-volatile semiconductor memory device, comprising:

• a memory cell array region including
• a plurality of memory cells arranged in rows and columns for storing data in a non-volatile manner,
• a plurality of word lines provided corresponding to the rows of said memory cells, and
• a plurality of bit lines provided corresponding to the columns of said memory cells;
• and
• a control unit controlling data writing to selected ones of said plurality of memory cells corresponding to selected one of said plurality of word lines as a target of said data writing,
• said control unit performing
• designation of a unit writing operation repeated until said data writing is completed,
• a first judging operation, conducted every time said unit writing operation is finished, to confirm whether said data writing is completed for at least one of said selected memory cells, and
• a second judging operation, conducted every time said unit writing operation is finished after said first judging operation has confirmed the completion of the data writing for the at least one of said selected memory cells, to confirm whether said data writing is completed for all said selected memory cells.