Author: David Jeffrey BurlesonPublisher:
ISBN:
Category :
Languages : en
Pages : 438
Book Description
The Chemical Vapor Deposition of Zirconium Dioxide from Zirconium Tetra-tert-butoxide and Zirconium Nitrate
Author: David Jeffrey BurlesonPublisher:
ISBN:
Category :
Languages : en
Pages : 438
Book Description
Fundamental Gas-phase and Surface Chemistry of Vapor-phase Deposition II and Process Control, Diagnostics and Modeling in Semiconductor Manufacturing IV
Author: Electrochemical Society. High Temperature Materials DivisionPublisher: The Electrochemical Society
ISBN: 9781566773195
Category : Science
Languages : en
Pages : 526
Book Description
The Chemical Vapor Depositions of HfO2 and HfO2/SiO2 Nanolaminates
Author: Curtiss Jae HellaDissertation Abstracts International
Author: Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 652
Book Description
Chemical Vapor Deposition and Characterization of Zirconia Films for High-k Dielectric Applications
Author: Zhe SongPublisher:
ISBN:
Category : Dielectric films
Languages : en
Pages : 0
Book Description
Due to the aggressive dimensional scaling of metal-oxide-semiconductor-field-effect-transistors (MOSFETs), direct tunneling current across the SiO2 gate dielectric layer has become a significant problem. High-k dielectric materials, such as ZrO2, HfO2, are expected to replace SiO2 as the gate dielectric layers to minimize direct tunneling currents. Development of the deposition processes and the characterization of high-k films have become significant challenges for the semiconductor industry. Based on multi-sample variable-angle spectroscopic ellipsometery (MS-VASE), we first developed a methodology to characterize ZrO2 films deposited on silicon. Results showed that proper modeling the optical properties of the interfacial layer is the key to accurate characterization. Using a stack model, consisting of an effective medium approximation (EMA) surface-roughness layer, a Tauc-Lorentz (TL) layer to represent the ZrO2 layer, and a second TL layer to represent the interfacial layer, we accurately extracted both thicknesses and optical constants of layers. The extracted surface-roughness and thickness values were confirmed by atomic force microscopy (AFM) and transmission electron microscopy (TEM) results. The following chapters cover studies of the initial-stage deposition of ZrO2 films from zirconium t-butoxide (ZTB) on both native silicon oxide and H-terminated silicon (H-Si) surfaces. In-situ SE was used to study the deposition process in real time. AFM, TEM, time of flight medium back scattering (ToF MEBS), and angle resolved X-ray photoelectron spectroscopy (ARXPS) were used to investigate the properties of deposited films. We discovered that film properties are affected by the nucleation and coalescence processes on different surfaces. A 3-dimensional nucleation process is predominant on H-Si surfaces due to the lack of reactive surface hydroxyl groups and high surface diffusivity of ZTB molecules. At temperatures about 350 °C, a layer-by-layer deposition process on native oxide surfaces leads to smooth, uniform ZrO2 films. An interfacial layer between the silicon substrate and ZrO2 is formed through two independent mechanisms: reaction between the starting surfaces and ZTB or its decomposition intermediates, and the diffusion of reactive oxidants through the forming ZrO2 interfacial stack layer and their reaction with the substrate.
Ultra-thin Zirconium Oxide Film Deposited by Rapid Thermal Chemical Vapor Deposition as an Alternative Gate Dielectric
Author: You-Sheng LinSurface Chemistry of Aerosolized, Size-selected Nanoparticles
Author: Amanda Marie NienowVaporization of Zirconium Oxide
Author: M. M. NakataPublisher:
ISBN:
Category : Vaporization, Heats of
Languages : en
Pages : 32
Book Description
Low Temperature Chemical Vapor Deposition of Zirconium Nitride in a Fluidized Bed
Author: Marie ArrietaPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The objective of this research was to design, assemble, and demonstrate the initial performance of a fluidized bed chemical vapor deposition (FB-CVD) system capable of producing thin, uniform zirconium nitride (ZrN) coatings (1 to 10 micrometers thick) on uranium-molybdenum (UMo) particulate fuel. Plate-type fuel with U-xMo (x = 3 to 10 wt.%) particle fuel dispersed in an aluminum matrix is under development at Idaho National Laboratory (INL) for the Reduced Enrichment for Research and Test Reactors (RERTR) program. Initial irradiation tests performed at INL in the Advanced Test Reactor (ATR) indicate an interaction layer forms between the fuel microspheres and the matrix at relatively high power levels. These power levels induce higher temperatures which enables uranium diffusion into the aluminum during irradiation, eventually causing fuel plate failure. The objective of this work was to create a process to mitigate the fuel/matrix interaction by forming a thin barrier coating on the surface of the U-xMo microspheres before incorporation into the dispersion fuel plate matrix. One of the main challenges in performance of the FB-CVD system was the effective fluidization of a powder whose physical characteristics (size, density) are continuously changing. To address this, two types of fluidized bed reaction vessels were designed and improved over the course of this research: a spouted fluidized bed and an inverted fluidized bed. Both reaction vessels utilized tetrakis(dimethylamino)zirconium (TDMAZ) and ammonia gas as precursors at atmospheric pressure. Tungsten wires and zirconia-silica (ZrO2-SiO2) microspheres were used as the substrates for the coating experiments. The substrate temperature and precursor gas flow were manipulated as the process variables. The FB-CVD system was successful in forming zirconium based coatings on surrogate microspheres with elevated levels of chemical impurities. At atmospheric pressure, coatings of thicknesses ranging from 0.5 micrometers to 1.5 micrometers were produced between temperatures of 250°C and 350°C. The deposited coatings were characterized using scanning electron microscopy, energy dispersive spectroscopy and wavelength dispersive spectroscopy.
Preparation of Zirconium from Zirconium Tetrafluoride
Author: C. J. BarochPublisher:
ISBN:
Category : Fluorides
Languages : en
Pages : 22
Book Description