An SRAM PUF with 2 Independent Bits/Cell in 65nm

Abstract

An SRAM Physical Unclonable Function (PUF) cell is fabricated and reported, which has two bits per cell. The Decision Voltage of the cell is analyzed and the cell is designed such that only the NMOS devices in the latch configuration contribute to the cell response. Either one of two pairs of NMOS devices is selected, such that two independent bits are generated. The cell was fabricated and measured in TSMC 65nm technology with a highly competitive area of 1420F <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> per bit.