A method for identifying an unclonable chip uses hardware intrinsic keys and authentication responses employing intrinsic parameters of memory cells invariant and unique to the unclonable chip, wherein intrinsic parameters that characterize the chip can extend over its lifetime. The memory cells having a charge-trap behavior are arranged in an NOR type memory array, allowing to create a physically unclonable fuse (PUF) generation using non-programmed memory cells, while stringing non-volatile bits in programmed memory cells. The non-volatile memory cell bits are used for error-correction-code (ECC) for the generated PUF. The invention can further include a public identification using non-volatile bits, allowing hand shaking authentication using computer with dynamic challenge.