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Resistive random access memory (RRAM) cells with a thin oxygen-deficient \ZrTiOx film topped by a Ti oxygen-gettering layer and a Pt electrode were fabricated on n-Ge layer, and the switching mechanism, as well as electrical characteristics, was explored. The RRAM cells demonstrate a stable bipolar switching behavior without the requirement of a forming process. Because of the existence of a larger amount of interface traps which would trap carriers and help build a favorable electric field for the drift of oxygen vacancies, the RRAM cells possess lower SET and RESET voltages compared to those fabricated on n-Si layer. With many promising properties such as a large sensing margin of 300 times, a high operation speed of 250 ns, a robust endurance of \10^5\ \cycles, and a long data retention time of up to 10 years, the \ZrTiOx-based RRAM cells exhibit a promising perspective as nonvolatile memory devices for Ge-based technology. [ABSTRACT FROM AUTHOR]

CF4 plasma treatment on germanium (Ge) surface is proposed in this work to alleviate the strong Fermi level pinning between metal/Ge, and its effectiveness is also explored for n- and p-type Ge wafers. It is found that samples with CF4 plasma treatment reveal conduction behavior transition between Schottky and ohmic characteristics, a metal-work-function-dependent Schottky barrier height as well as modulated contact resistance, and these results confirm the depinning of Fermi level. This depinning can be explained by the effective capability in passivating dangling bonds at Ge surface through fluorine atoms and the formation of Ge-F binding with partial ionic property, both of which are helpful in decreasing the number of surface states and consequently release the pinning effect. [ABSTRACT FROM AUTHOR]

A Ge-stabilized tetragonal ZrO2 dielectric with a permittivity (κ) value of 36.5 has been obtained by annealing a ZrO2/Ge/ZrO2 laminate at 500 °C and it is a more reliable approach toward stabilizing a tetragonal ZrO2 film. However, metal-insulator-metal (MIM) capacitors with the sole tetragonal ZrO2 film as an insulator achieve a high capacitance density of 27.8 fF/μm2 at the price of a degraded quadratic voltage coefficient of capacitance (VCC) of 81 129 ppm/V2 and unacceptably high leakage current. By capping an amorphous La-doped ZrO2 layer with a κ value of 26.3 to block grain boundaries-induced leakage paths of the crystalline ZrO2 dielectric, high-performance MIM capacitors in terms of a capacitance density of 19.8 fF/μm2, a VCC of 3135 ppm/V2, leakage current of 6.5×10-8 A/cm2 at -1 V, as well as a satisfactory capacitance change of 1.21% after ten-year operation can be realized. [ABSTRACT FROM AUTHOR]

[•] The YGeO x enjoys a low interface trap density of 2.1×1011 cm−2 eV−1. [•] Low leakage current of 3.1×10−10 A/cm2 at the effective electric field of 1MV/cm. [•] 13mV flatband voltage shift for BTI test under 10MV/cm for 8000s at 85°C. [ABSTRACT FROM AUTHOR]

Abstract: A Ge-stabilized tetragonal ZrO2 (t-ZrO2) film with permittivity (κ) of 36.2 was formed by depositing a ZrO2/Ge/ZrO2 laminate and a subsequent annealing at 600°C, which is a more reliable approach to control the incorporated amount of Ge in ZrO2. On Si substrates, with thin SiON as an interfacial layer, the SiON/t-ZrO2 gate stack with equivalent oxide thickness (EOT) of 1.75nm shows tiny amount of hysteresis and negligible frequency dispersion in capacitance–voltage (C–V) characteristics. By passivating leaky channels derived from grain boundaries with NH3 plasma, good leakage current of 4.8×10−8 A/cm2 at V g = V fb −1V is achieved and desirable reliability confirmed by positive bias temperature instability (PBTI) test is also obtained. [Copyright &y& Elsevier]