Semiconductor device identifier generation method and semiconductor device

Abstract

A method () is disclosed of generating an identifier from a semiconductor device () comprising a volatile memory () having a plurality of memory cells. The method comprises causing () the memory cells to assume a plurality of pseudo-random bit values inherent to variations in the microstructure of the memory cells; retrieving () the bit values from at least a subset of the plurality of memory cells; and generating the identifier from the retrieved bit values. The method () is based on the realization that a substantial amount of the cells of a volatile memory can assume a bit value that is governed by underlying variations in manufacturing process parameters; this for instance occurs at power-up for an SRAM or after a time period without refresh for a DRAM. This can be used for several identification purposes, such as identifying a semiconductor device () comprising the volatile memory (), or for secure key generation by mapping error-correcting code words onto the identifier bit locations. The present invention further includes a semiconductor device () configured to be subjectable to the method () of the present invention.