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Resistive switching memory (RRAM) features many optimal properties for future memory applications that make RRAM a strong candidate for storage-class memory and embedded nonvolatile memory. This paper addresses the cycling-induced degradation of RRAM devices based on a HfO2 switching layer. We show that the cycling degradation results in the decrease of several RRAM parameters, such as the resistance of the low-resistance state, the set voltage V\mathrm{ set} , the reset voltage V\mathrm{ reset} , and others. The degradation with cycling is further attributed to enhanced ion mobility due to defect generation within the active filament area in the RRAM device. A distributed-energy model is developed to simulate the degradation kinetics and support our physical interpretation. This paper provides an efficient methodology to predict device degradation after any arbitrary number of cycles and allows for wear leveling in memory array. [ABSTRACT FROM AUTHOR]

In conventional integrated circuit technologies, a grounded metal guard ring (MGR) is widely used to mitigate the coupling effect between any pair of inductors. Full-wave electromagnetic (EM) simulation results indicate that the guard ring size can significantly affect the inductance value of a single-turn planar inductor. This paper proposes a switchable artificial grounded MGR technique that can not only serve as a guard ring but also change the inductance. Accordingly, an inductor, featuring switchable inductance and high quality factor, is developed for a 60-GHz millimeter-wave wide-frequency tuning range (wide-FTR) and low phase-noise voltage-controlled oscillator (VCO) in 90-nm bulk CMOS technology. The VCO testkey achieves a total tuning range of 9.43 GHz (17%). The measured phase noise levels are -92.2 and -119 dBc/Hz at 1- and 10-MHz offsets, respectively. The experimental results demonstrate that the proposed inductor topology offers the VCO an increase of 36% in the FTR and a competitive performance in phase noise, as contrasted with a conventional varactor-tuned VCO. This VCO achieves a record of -188 dBc/Hz for the \FOMT. [ABSTRACT FROM PUBLISHER]

Resistive switching memory (RRAM) devices generally rely on the formation/dissolution of conductive filaments through insulating materials, such as metal oxides and chalcogenide glasses. Understanding the mechanisms for filament formation and disruption in resistive switching materials is a critical step toward the development of reliable and controllable RRAM for future-generation storage. In particular, the capability to control the filament resistance and the reset current through the compliance current during filament formation may provide a key signature to clarify the switching mechanism. This paper provides a physically based explanation for the universal resistance switching in bipolar RRAM devices. A numerical model of filament growth based on thermally activated ion migration accounts for the resistance switching characteristics. The same physical picture is extended to numerically model the reset transition. The impact of migration parameters and experimental setup on the set/reset characteristics is discussed through numerical simulations. [ABSTRACT FROM AUTHOR]

The need for reliable models that take into account the nonlinear kinetics of dopants is nowadays of paramount importance, particularly with the physical dimensions of electron devices shrinking to the deep nanoscale range and the development of emerging nanoionic systems such as the memristor. In this paper, we present a novel nonlinear dopant drift model that resolves the boundary issues existing in previously reported models that can be easily adjusted to match the dynamics of distinct memristive elements. With the aid of this model, we examine switching mechanisms, current–voltage characteristics, and the collective ion transport in two terminal memristive devices, providing new insights on memristive behavior. [ABSTRACT FROM PUBLISHER]

This paper presents, for the first time, the study of the application of a lateral diffused metal–oxide–semiconductor field-effect transistor (LDMOSFET) in a common-gate configuration to radio-frequency (RF) transmit/receive (T/R) switching circuits. A single-pole double-throw (SPDT) 900-MHz T/R switch is implemented using 0.25-\mu\m LDMOSFET foundry technology. Measured results show that our switching circuit can achieve a low insertion loss of 0.82 dB and a high power handling capability of 27 dBm. This result is promising in integrating power management integrated circuits, RF power amplifiers, and switching circuits in a single chip, based on LDMOSFET technology, to realize an RF transmit front-end system-on-chip solution. [ABSTRACT FROM AUTHOR]