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The Stopping Power of Amorphous and Channelled Silicon at All Energies as Computed with the Binary Encounter Approximation

Description: This thesis utilizes the binary encounter approximation to calculate the stopping power of protons penetrating silicon. The main goal of the research was to make predictions of the stopping power of silicon for low-energy and medium-energy channelled protons, in the hope that this will motivate experiments to test the theory developed below. In attaining this goal, different stopping power theories were compared and the binary encounter approach was applied to random (non-channelled) and high-e… more
Date: December 1994
Creator: Bickel, David, 1970-
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Evolution of Vacancy Supersaturations in MeV Si Implanted Silicon

Description: High-energy Si implantation into silicon creates a net defect distribution that is characterized by an excess of interstitials near the projected range and a simultaneous excess of vacancies closer to the surface. This defect distribution is due to the spatial separation between the distributions of interstitials and vacancies created by the forward momentum transferred from the implanted ion to the lattice atom. This dissertation investigates the evolution of the near-surface vacancy excess in… more
Date: May 1999
Creator: Venezia, Vincent C.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Influence of design and coatings on the mechanical reliability of semiconductor wafers.

Description: We investigate some of the mechanical design factors of wafers and the effect on strength. Thin, solid, pre-stressed films are proposed as a means to improve the bulk mechanical properties of a wafer. Three-point bending was used to evaluate the laser scribe density and chemical processing effect on wafer strength. Drop and strike tests were employed to investigate the edge bevel profile effect on the mechanical properties of the wafer. To characterize the effect of thin films on stren… more
Date: August 2002
Creator: Yoder, Karl J.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Silenes and Silenoids in the Chemistry of Cyclopentadienylsilanes

Description: Evidence is presented that apparent silene products obtained from the metalation of cyclopentadienyldimethyl - chlorosilane either with tert-butyl1ithium or with methylenetriphenylphosphorane actually arise from the metalated starting material, a silenoid, rather than from a silafulvene intermediate. Trimethylmethoxysi1ane is shown to be an effective trap for dimethylsilafulvene. A new dimethylsilafulvene precursor, bis(dimethylmethoxysi1yl) cyclopentadiene, which gives high yields of dimethyld… more
Date: August 1986
Creator: Rozell, James M. (James Morris)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Thermal Reactions of Four-Membered Rings Containing Silicon or Germanium

Description: The synthesis of E- and Z-1,1,2,3-tetramethylsilacyclobutanes is described. Pyrolysis of either isomer at 398.2 °C provides the same products but in different amounts: propene, E- and Z-2-butene, allylethyldimethylsilane, dimethylpropylsilane, the respective geometric isomers, 1,1,2,3,3-pentamethyl-1,3-disilacyclobutane, 1,1, l-ethyldimethyl-2,2,2-vinyldimethyl-disilane and E- and Z-1,1,2,3,3,4-hexamethyl-1,3-disilacyclobutane. Mechanisms involving di- and trimethylsilenes are described for dis… more
Date: December 1988
Creator: Namavari, Mohammad, 1950-
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Performance of Silicon Based Sensor and its Application in Silver Toxicity Studies

Description: The silicon based sensor is able to detect part per trillion ionic silver in 0.0098% hydrofluoric acid based on the open circuit potential (OCP) measurement. The OCP jump of 100 ppt ionic silver solution is up to 120 mV. The complex agent can effectively suppress the ionic silver concentration and suppress the OCP signal. The ability of complex agent to suppress the OCP signal depends on the formation constant of the complex with silver. The complex adsorbed on the sensor surface induces a sec… more
Date: August 2000
Creator: Peng, Haiqing
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Survey of Refractory Uranium Compounds

Description: Abstract: Chemical and physical data on twenty binary uranium compounds that may prove suitable for refractory nuclear fuels were assembled. The compounds were those with aluminum, boron, carbon, iron, nickel, nitrogen, silicon, or sulfur. Too little is known at this time about the compounds to evaluate any of them for fuel. The program is being extended in an effort to provide the needed data.
Date: August 7, 1956
Creator: Loch, Luther D.; Engle, Glen B.; Snyder, M. Jack & Duckworth, Winston Howard
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Systematic Approaches to Predictive Computational Chemistry using the Correlation Consistent Basis Sets

Description: The development of the correlation consistent basis sets, cc-pVnZ (where n = D, T, Q, etc.) have allowed for the systematic elucidation of the intrinsic accuracy of ab initio quantum chemical methods. In density functional theory (DFT), where the cc-pVnZ basis sets are not necessarily optimal in their current form, the elucidation of the intrinsic accuracy of DFT methods cannot always be accomplished. This dissertation outlines investigations into the basis set requirements for DFT and how the … more
Date: May 2009
Creator: Prascher, Brian P.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Chemistry, Detection, and Control of Metals during Silicon Processing

Description: This dissertation focuses on the chemistry, detection, and control of metals and metal contaminants during manufacturing of integrated circuits (ICs) on silicon wafers. Chapter 1 begins with an overview of IC manufacturing, including discussion of the common aqueous cleaning solutions, metallization processes, and analytical techniques that will be investigated in subsequent chapters. Chapter 2 covers initial investigations into the chemistry of the SC2 clean - a mixture of HCl, H2O2, and DI wa… more
Date: May 2005
Creator: Hurd, Trace Q.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Investigation of Selected Optically-Active Nanosystems Fashioned using Ion Implantation

Description: Opto-electronic semiconductor technology continues to grow at an accelerated pace, as the industry seeks to perfect devices such as light emitting diodes for purposes of optical processing and communication. A strive for greater efficiency with shrinking device dimensions, continually pushes the technology from both a design and materials aspect. Nanosystems such a quantum dots, also face new material engineering challenges as they enter the realm of quantum mechanics, with each system and ma… more
Date: May 2006
Creator: Mitchell, Lee
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries

Interfacial Studies of Bimetallic Corrosion in Copper/Ruthenium Systems and Silicon Surface Modification with Organic and Organometallic Chemistry

Description: To form Cu interconnects, dual-damascene techniques like chemical mechanical planarization (CMP) and post-CMP became inevitable for removing the "overburden" Cu and for planarizing the wafer surface. During the CMP processing, Cu interconnects and barrier metal layers experience different electrochemical interactions depending on the slurry composition, pH, and ohmic contact with adjacent metal layers that would set corrosion process. Ruthenium as a replacement of existing diffusion barrier lay… more
Access: Restricted to the UNT Community Members at a UNT Libraries Location.
Date: August 2006
Creator: Nalla, Praveen Reddy
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

The Molybdenum Blue Reaction and the Determination of Phosphorus in Waters Containing Arsenic, Silicon, and Germanium

Description: Report discussing studies on the molybdenum blue reaction and the determination of phosphorus in waters containing arsenic, germanium, and silicon. Experimental methods and data are included.
Date: November 1953
Creator: Levine, Harry; Rowe, J. J. & Grimaldi, F. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High Sensitivity Measurement of Implanted as in the Presence of Ge in Ge(x)Si(1-x)/Si Layered Alloys Using Trace Element Accelerator Mass Spectrometry

Description: This article discusses high sensitivity measurement of implanted As in the presence of Ge in Ge(x)Si(1-x)/Si layered alloys using trace element accelerator mass spectrometry.
Date: December 11, 2000
Creator: Datar, Sameer A.; Wu, Liying; Guo, Baonian N.; Nigam, Mohit; Necsoiu, Daniela; Zhai, Y. J. et al.
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences
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Low-level copper concentration measurements in silicon wafers using trace-element accelerator mass spectrometry

Description: This article discusses low-level copper concentration measurements in silicon wafers using trace-element accelerator mass spectrometry.
Date: June 8, 1998
Creator: McDaniel, Floyd Del. (Floyd Delbert), 1942-; Datar, Sameer A.; Guo, Baonian N.; Renfrow, Steve N.; Anthony, J. M. & Zhao, Z. Y.
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences
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Microstructure Studies of Silicon-on-Insulator for Very Large Scale Integrated Circuit Applications

Description: Silicon-on-insulator formed by high dose oxygen ion implantation and subsequent epitaxially grown silicon layers were studied and compared with silicon on sapphire materials. Czochralski grown, (100) silicon wafers were implanted with molecular oxygen ions, 0+2, to a total dose of 2.12 x 10^18 0+/cm^2 at an energy of 150 keV/atom.
Date: December 1982
Creator: Hamdi, Aboud Helal
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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