Method for localizing point defects causing leakage currents in a non-volatile memory device

Method for localizing point defects causing column leakage currents in a non-volatile memory device including a plurality of memory cells arranged in rows and columns in a matrix structure, source diffusions, and metal lines which connect said source diffusions to each other. Such a method includes the steps of: modifying the memory device in order to make source diffusions independent of each other and each one electrically connected to a respective row; sequentially biasing the single columns of the matrix; localizing the column to which at least one defective cell belongs, as soon as the leakage current flow occurs in the biased column; by keeping biased the localized column, biasing sequentially the single rows of the matrix to the same potential as that of the localized column; localizing a couple of cells, wherein at least one of them involves the point defects, as soon as the leakage current flow does not occur.