A trade-off between the memory window and the endurance exists for transition-metal-oxide RRAM. In this work, we demonstrated that HfO_x/Ge-based metal-insulator-semiconductor RRAM devices possess both a larger memory window and longer endurance compared with metal-insulator-metal (MIM) RRAM devices. Under DC cycling, HfO_x/Ge devices exhibit a 100× larger memory window compared to HfO_x MIM devices, and a DC sweep of up to 20,000 cycles was achieved with the devices. The devices also realize low static power down to 1 nW as FPGA’s pull-up/pull-down resistors. Thus, HfO_x/Ge devices act as a promising candidates for various applications such as FPGA or compute-in-memory, in which both a high ON/OFF ratio and decent endurance are required.

In this work, we investigate the self-rectifying behaviors of the resistive random access memory (RRAM) fabricated on n-Ge substrates, featuring an ultrahigh rectifying ratio ( $>$ 10 $^{\text{5}}$ ), a high ON/OFF ratio ( $>$ 500), and low operation voltages. The excellent performances of the Ge-based RRAM in this study are attributed to the Fermi-level pinning (FLP) near the valence band edge of n-Ge through the localized conductive filaments in HfO $_{\text{2}}$ . In addition, the underlying mechanism of the FLP behaviors in RRAM on n-Ge substrates is discussed. The electrical properties of the self-rectifying RRAM, including superior data retention, excellent uniformity, decent switching speed, endurance, and robust read/write disturbance immunity, are characterized comprehensively. The FLP-induced superior rectifying behaviors and excellent electrical properties of the RRAM enable the potential application of the high-density nonvolatile memory.

This study experimentally investigated La-doped ZrO₂ (ZLO) antiferroelectric (AFE) capacitors. Significant polarization enhancement is demonstrated in ZLO antiferroelectric capacitors with the optimized La concentration. The ZLO antiferroelectric capacitors reveal superior performance even under a low-temperature process (10¹⁰ cycles). The results in this study opens new avenues for practical antiferroelectric applications and brings promise for their integration into advanced integrated circuits.