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In this work, SiCxNy-based resistive switching memory by using a single precursor for the back end of line (BEOL) integration has been investigated. SiCxNy films were deposited on the aluminum (Al) substrates using plasma enhanced atomic layer deposition (PEALD) method. The effects of SiCxNy chemical structure with respect to resistive switching characteristics have been studied, and the results suggest that the resistive switching mechanism is dominated by the interfacial Schottky junction with SiCxNy composition. This work not only demonstrates a PEALD method in fabricating SiCxNy-based electronics active devices but also provides additional insights into the interaction between the electrical and chemical structures in bi-functional resistive switching or threshold switching behavior. A demonstrated PEALD tool with simple single-precursor for SiCxNy deposition shows excellent feasibility to be used as functional memory and selector devices, further giving the potential pathway for advanced BEOL process integration.

Highly crystalline thin films of MoS2 were prepared over large area by pulsed laser deposition down to a single monolayer on Al2O3 (0001), GaN (0001), and SiC-6H (0001) substrates. X-ray diffraction and selected area electron diffraction studies show that the films are quasi-epitaxial with good out-of-plane texture. In addition, the thin films were observed to be highly crystalline with rocking curve full width half maxima of 0.01°, smooth with a RMS roughness of 0.27 nm, and uniform in thickness based on Raman spectroscopy. From transport measurements, the as-grown films were found to be p-type.

Nanostructure band engineering accomplished by CF4 plasma treatment on Gd2O3 nanocrystal memory was investigated. Under the CF4 plasma treatment, the fluorine was incorporated into the Gd2O3 film and resulted in the modification of energy-band. A physical model was proposed to explain the relationship between the built-in electric field in Gd2O3 nanostructure and the improved program/erase (P/E) efficiency and data retention characteristics. The memory window of the Gd2O3–NC memory with CF4 plasma treatment and postplasma annealing was increased to 3.4 V after 104 P/E cycling. It is demonstrated that the Gd2O3–NC memory with nanostructure band engineering is promising for future nonvolatile memory application.

In response to harmonic forces generated by the heart, the arterial system executes strong coupled distributed oscillatory motions. These oscillations are described by a pressure-area wave equation, which is solvable subject to appropriate Sturm–Liouville boundary conditions. The response pressure can be represented as a sum of stationary waves which are the eigenmodes of the whole arterial system. Natural frequencies of the system are related to the eigenvalues and the phase velocity. Matching of these natural frequencies with heart rate or its harmonics is important in ventricular-arterial coupling. Transfer functions for the pressure can be constructed from the corresponding eigenfunctions.

A soluble organic material, polyacrylonitrile (PAN), was investigated for its feasibility of gate dielectric applications. The solution-processed PAN was spin coated in air. Results show that leakage current density as low as 0.3nA∕cm2 for 50nm PAN dielectrics could be achieved via process optimization. Functional transistor characteristics were achieved in air for the implementation of PAN in organic thin-film transistors using pentacene or poly(3-hexylthiophene) as a semiconductor material.

In a spin‐wave instability experiment, a YIG disk was bonded onto a quartz rod with a transducer attached to it, and was placed in a microwave cavity in a parallel‐pumping arrangement. For microwave power above the threshold for spin‐wave instability, parametric generation of acoustic waves was observed. The generation was evidenced by the simultaneous appearance of a low‐frequency oscillation in the reflected microwave power and at the transducer. In a subsequent experiment, a low‐frequency acoustic wave was sent into YIG through the transducer. A great enhancement of the oscillation in the reflected microwave power was observed. The enhancement was due to phase‐locking of spin‐wave modes.

Spin‐wave spectrum in an instability and mode‐locking experiment was observed by using a spectrum analyzer. The experiment confirms that spin‐wave side bands exist. The beating of the side bands with the central band is shown to be the cause for low‐frequency modulation of the reflected microwave power. When a low‐frequency acoustic wave was sent into the sample, the amplitude of the side bands increased at the expense of the central band. Therefore, the effect of magnetoelastic coupling can be used not only to lock the phases of the various spin‐wave modes but also to regulate their amplitudes.