Impact of random telegraph signals on Vmin in 45nm SRAM

An alternating-bias random telegraph signal (RTS) characterization technique is presented, which shortens measurement time by 10× and also produces more accurate statistical distributions of RTS amplitudes. Measurements of RTS amplitudes in 45 nm SRAM transistor Ids and cell write margin are reported and used to demonstrate a complex dependence of write margin on RTS in multiple transistors. Fail bit rate of SRAM with RTS is estimated using a statistical model populated by Iwrite measurements. Statistical analysis indicates a Vmin degradation of less than 50 mV due to RTS.