A Reflow-capable, Embedded 8Mb STT-MRAM Macro with 9nS Read Access Time in 16nm FinFET Logic CMOS Process

In this paper, we present the design and silicon characterization results of an 8Mb STT-MRAM macro in 16nm FinFET Logic CMOS process. The STT-MRAM film stack is carefully designed to achieve both solder-reflow tolerance and short write pulse of 50nS. A merged reference scheme with reverse connected reference cells are proposed for read-disturb immunity. A read access time of 9nS is achieved from -40C to 125C and Vdd=0.8V±10%, making it suitable for high performance MCU applications. Silicon data measurement is presented to demonstrate a logic-process compatible, perpendicular STT-MRAM in 16nm FinFET CMOS process. The bit-error-rate has achieved zero fail-bit-count at 50-percentile for the 8Mb test-chip at wafer level.