The Amplitude and phase of surface acoustic waves can be characterized using a laser beam and photodiode detector. This paper describes a technigue for charactarizing waves using the double photodiode method. This method is a modification of the knife-edge method, and involves focusing a laser beam to a beam spot...
Radiation studies were performed on compound semiconductor heterostructure devices. The objective was to understand the degradation processes caused by the exposure of these devices to radiation. Preliminary experiments were focussed on studying the degradation phenomenon in single heterojunctions and single quantum wells. It was found that ionizing radiation like gamma...
The advent of low-cost RFIC's fabricated in Silicon-based technologies has led to the use of monolithic lumped elements which are located on-die. While it is clearly advantageous to have a high degree of integration and thus fewer off chip elements, parasitic losses due to semiconducting substrate effects can be a...
The electrical performance of on-chip interconnects has become a limiting factor to the performance of modern integrated circuits including RFICs, mixed-signal circuits, as well as high-speed VLSI circuits due to increasing operating frequencies, chip areas, and integration densities. It is advantageous to have fast and accurate closed-form expressions for the...
In high-frequency circuit design, performance is often limited by the quality of the passive components available for a particular process. Specifically, spiral inductors can be a major bottle-neck for Voltage-Controlled Oscillators (VCOs), Low-Noise Amplifiers (LNAs), mixers, etc. For designers to correctly optimize a circuit using a spiral inductor, several frequency-domain...
A new method for accelerating the Upstream Corner Balance (UCB) discretization of the equation of transfer is introduced. The inconsistent acceleration equations for the UCB discretization are derived by applying the "Modified 4-Step" diffusion synthetic acceleration technique not to the UCB discretization, but instead to the simple corner balance (SCB)...
Imaging spectra of plant tissues yield considerable potential and useful information
for basic studies and agriculture practice. We constructed an imaging spectrophotometer
with spectral range from 400 nm to 1100 nm, which was used to study various
physiological events of plant germplasm: location of bundle sheath and mesophyll cells in...
Nanolaminate dielectrics combine two or more insulating materials in a many-layered film. These structures can be made to significantly outperform films composed of a single one of their constituent materials by adjusting the composition ratio, arrangement, and size of the component layers. In this work, atomic layer deposition (ALD) is...
As the semiconductor industry works to integrate increasingly more "non-CMOS" devices onto CMOS ICs, compact model development has become an important step in the circuit/system verification tool flow. This research focuses on the two- and three-dimensional modeling of the physical phenomena that occur in nanoscale magnetic devices. This includes the...
This thesis presents two new approaches for the broadband, time-domain modeling of lossy transmission lines. Each approach is based on an alternative derivation of delay extraction in order to separate the line's linear phase from its
attenuation and dispersion. Augmentation networks represent the derived attenuation networks as rational function approximations....
The desire to apply short-range wireless communication systems to telemetry sensor networks in a metal-enclosed chamber has prompted this study. This thesis will discuss the design of an infrared (IR) communication system for a wireless low-power, low-data- rate sensor network in a metal enclosure. This design requires an in-depth understanding...
The problem of locating a signal source, or an emitter, has many civilian and military applications, such as communication regulations enforcement, military reconnaissance, and search-and-rescue operations. Many of the most widely used emitter location methods rely on the accurate and robust estimation of the differential time delay,
or time-difference-of-arrival (TDOA),...
The atomic solid state energy (SSE) scale is introduced as a tool for inorganic materials design. The SSE scale is obtained by assessing an average electron affinity (EA) (for a cation) or an average ionization potential (IP) (for an anion) for each atom using data from compounds having that specific...
Fabrication techniques and process integration considerations for amorphous oxide semiconductor (AOS) thin-film transistors (TFTs) constitute the central theme of this dissertation. Within this theme three primary areas of focus are pursued.
The first focus involves formulating a general framework for assessing passivation. Avoiding formation of an undesirable backside accumulation layer...
Spiral inductors are a key component of mixed-signal and analog integrated circuits (IC's). Such circuits are often fabricated using silicon-based technology, owing to the inherent low-cost and high volume production aspects. However, semiconducting substrate materials such as silicon can have adverse effects on spiral inductor performance due to the lossy...
The central focus of this thesis is the design, fabrication and characterization of amorphous oxide semiconductor (AOS) thin-film transistor (TFT) current mirrors. The thin-film deposition and circuit fabrication methods used to realize zinc tin oxide (ZTO) TFT
current mirrors are addressed in order to elucidate the processing challenges for this...
Real-time, high efficiency neutron spectroscopy has, historically, been a persistent challenge in the field of radiation detection and, for the most part, has gone unsolved. The most promising method to resolve this challenge, is the boron-capture technique using an organic scintillation system (BC-523a). Detectors that utilize this method possess an...
The aim of this dissertation is to develop oxide semiconductors by radio-frequency
sputtering for thin-film transistor (TFT) applications. A variety of oxide semiconductors
are used as the TFT channel layer, including indium gallium oxide (IGO), zinc tin
oxide (ZTO), and indium gallium zinc oxide (IGZO). The variety of materials used...