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open access

Si Memory Chip as a Sensitive Neutron Detector

Description: A novel neutron detector is based on semiconductor technology. A boron-containing film is an integral part of the semiconductor device and is in physical contact with the charge-storage medium (CSM). The CSM is a proprietary cell design known as MirrorBit{trademark}, which is different from conventional memory designs such as SRAM or DRAM. The design doubles the resolution and sensitivity in the array. This enables a highly effective detection of the secondary particles, {sup 7}Li and {sup 4}He… more
Date: March 1, 2008
Creator: Quam, William
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Design of Shallow P-Type Dopants in ZnO: Preprint

Description: This paper describes approaches to lower the acceptor ionization energy in ZnO by codoping acceptors with donor or isovalent atoms and proposes a universal approach to overcome the doping polarity problem for wide-band-gap semiconductors.
Date: May 1, 2008
Creator: Wei, S.-H.; Li, J. & Yan, Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Inverted GaInP/(In)GaAs/InGaAs Triple-Junction Solar Cells with Low-Stress Metamorphic Bottom Junctions: Preprint

Description: We demonstrate high efficiency performance in two ultra-thin, Ge-free III-V semiconductor triple-junction solar cell device designs grown in an inverted configuration. Low-stress metamorphic junctions were engineered to achieve excellent photovoltaic performance with less than 3 x 106 cm-2 threading dislocations. The first design with band gaps of 1.83/1.40/1.00 eV, containing a single metamorphic junction, achieved 33.8% and 39.2% efficiencies under the standard one-sun global spectrum and con… more
Date: May 1, 2008
Creator: Geisz, J. F.; Kurtz, S. R.; Wanlass, M. W.; Ward, J. S.; Duda, A.; Friedman, D. J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Photoelectrochemistry of Semiconductor Nanowire Arrays

Description: This project supported research on the growth and photoelectrochemical characterization of semiconductor nanowire arrays, and on the development of catalytic materials for visible light water splitting to produce hydrogen and oxygen. Silicon nanowires were grown in the pores of anodic aluminum oxide films by the vapor-liquid-solid technique and were characterized electrochemically. Because adventitious doping from the membrane led to high dark currents, silicon nanowire arrays were then grown o… more
Date: November 10, 2009
Creator: Mallouk, Thomas E & Redwing, Joan M
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Thin Film Solar Cells Derived from Sintered Semiconductor Quantum Dots: Cooperative Research and Development Final Report, CRADA number CRD-07-00226

Description: The NREL/Evident team will develop techniques to fabricate thin film solar cells where the absorption layers comprising the solar cells are derived from sintered semiconductor quantum dots.
Date: July 1, 2010
Creator: Ginley, D. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Time-Resolved Photoluminescence and Photovoltaics

Description: The time-resolved photoluminescence (TRPL) technique and its ability to characterize recombination in bulk photovoltaic semiconductor materials are reviewed. Results from a variety of materials and a few recent studies are summarized and compared.
Date: January 1, 2005
Creator: Metzger, W. K.; Ahrenkiel, R. K.; Dippo, P.; Geisz, J.; Wanlass, M. W. & Kurtz, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

MEASUREMENT OF NANOSTRUCTURES WITH MICROMACHINED MICROSCOPES

Description: We have made reproducible scanning probes with high efficiency, and predictable and reproducible character-istics. We obtained good efficiency with dimensions well below the diffraction limit, so that rela-tively small laser powers in the milliwatt range can be used. For single frequency operation, only low power is necessary to obtain very high fields for the excitation of well-defined Raman scattering, and to work in a reflection mode with good scanning speeds; obtained predictable results wi… more
Date: April 30, 2005
Creator: KINO, G.S. & MOERNER, W.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Nanostructure Arrays for Multijunction Solar Cells: Final Subcontract Report, 12 May 1999--11 July 2002

Description: This project developed the process technologies for the fabrication of high-efficiency multijunction photovoltaic cells using semiconductor nanostructure arrays. These devices are expected to provide increased energy conversion efficiency, as well as increased carrier collection efficiency. In addition, this approach provides the ability to tune the absorption spectrum to match selected windows of the solar spectrum. At the same time, these devices can be fabricated using existing industrial el… more
Date: June 1, 2004
Creator: Das, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Hybrid Nanorod-Polymer Solar Cell: Final Report; 19 July 1999--19 September 2002

Description: With the support of this grant, we successfully demonstrated that semiconductor nanorods can be used to fabricate readily processed and efficient hybrid solar cells together with polymers. By controlling nanorod length, we changed the distance over which electrons are transported directly through the thin-film device. Tuning the bandgap by altering the nanorod radius enabled us to optimize the overlap between the absorption spectrum of the cell and the solar emission spectrum. A photovoltaic de… more
Date: August 1, 2003
Creator: Alivisatos, A. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Optical Probe for Semiconductor: Cooperative Research and Development Final Report, CRADA Number CRD-06-206

Description: This CRADA involves development of a new semiconductor characterization tool, Optical Probe, which can be commercialized by GT Solar. GT Solar will participate in the design and testing of this instrument that will be developed under an IPP project.
Date: February 1, 2011
Creator: Sopori, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

High Temperature Water as an Etch and Clean for SiO2 and Si3N4

Description: An environmentally friendly, and contamination free process for etching and cleaning semiconductors is critical to future of the IC industry. Under the right conditions, water has the ability to meet these requirements. Water becomes more reactive as a function of temperature in part because the number of hydronium and hydroxyl ions increase. As water approaches its boiling point, the concentration of these species increases over seven times their concentrations at room temperature. At 150 °C, … more
Date: December 2018
Creator: Barclay, Joshua David
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Bistability of Cation Interstitials in II-VI Semiconductors

Description: The stability of cation interstitials in II-VI semiconductors is studied using ab initio methods. We find that interstitials in the neutral charge state are more stable in the tetrahedral interstitial site near the cation, whereas in the (2+) charge state, they are more stable near the anion. The diffusion energy barrier changes when the defect charge state changes. Therefore, if electrons/holes are taken from the defect level by light, changing its charge state, the interstitial atom will be a… more
Date: November 1, 2005
Creator: Wei, S. H. & Dalpian, G. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Research Leading to High Throughput Manufacturing of Thin-Film CdTe PV Modules: Annual Subcontract Report, September 2004--September 2005

Description: Specific overall objectives of this subcontract are improvement in baseline field performance of manufactured CdTe PV modules while reducing environmental, health and safety risk in the manufacturing environment. Project objectives focus on four broad categories: (1) development of advanced front-contact window layers, (2) improved semiconductor film deposition, (3) development of improved accelerated life test procedures that indicate baseline field performance, and (4) reduction of cadmium-re… more
Date: April 1, 2006
Creator: Powell, R. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Polymer Based Nanocomposites for Solar Energy Conversion

Description: Organic semiconductor-based photovoltaic devices offer the promise of low cost photovoltaic technology that can be manufactured via large-scale, roll-to-roll printing techniques. Existing organic photovoltaic devices are currently limited to solar power conversion efficiencies of 3?5%. This is because of poor overlap between the absorption spectrum of the organic chromophores and the solar spectrum, non-ideal band alignment between the donor and acceptor species, and low charge carrier mobiliti… more
Date: January 1, 2005
Creator: Shaheen, S.; Olson, D.; White, M.; Mitchell, W.; Miedaner, A.; Curtis, C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Electrostatic Effects in III-V Semiconductor Based Metal-optical Nanostructures

Description: The modification of the band edge or emission energy of semiconductor quantum well light emitters due to image charge induced phenomenon is an emerging field of study. This effect observed in quantum well light emitters is critical for all metal-optics based light emitters including plasmonics, or nanometallic electrode based light emitters. This dissertation presents, for the first time, a systematic study of the image charge effect on semiconductor–metal systems. the necessity of introducing … more
Date: May 2012
Creator: Gryczynski, Karol Grzegorz
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Chromic mechanism in amorphous WO{sub 3} films

Description: The authors propose a new model for the chromic mechanism in amorphous tungsten oxide films (WO{sub 3{minus}y}{center_dot}nH{sub 2}O). This model not only explains a variety of seemingly conflicting experimental results reported in the literature that cannot be explained by existing models, it also has practical implications with respect to improving the coloring efficiency and durability of electrochromic devices. According to this model, a typical as-deposited tungsten oxide film has tungsten… more
Date: November 1, 1996
Creator: Zhang, J. G.; Benson, D. K.; Tracy, C. E.; Deb, S. K.; Czanderna, A. W. & Bechinger, C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Advanced numerical methods and software approaches for semiconductor device simulation

Description: In this article the authors concisely present several modern strategies that are applicable to drift-dominated carrier transport in higher-order deterministic models such as the drift-diffusion, hydrodynamic, and quantum hydrodynamic systems. The approaches include extensions of upwind and artificial dissipation schemes, generalization of the traditional Scharfetter-Gummel approach, Petrov-Galerkin and streamline-upwind Petrov Galerkin (SUPG), entropy variables, transformations, least-squares m… more
Date: March 23, 2000
Creator: CAREY,GRAHAM F.; PARDHANANI,A.L. & BOVA,STEVEN W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A low-cost approach to fabrication of multinary compounds for energy-related applications

Description: Non-vacuum electrodeposition and electroless deposition techniques with a potential to prepare large-area uniform precursor films using low-cost source materials and low-cost capital equipment are very attractive for the growth of compound materials for superconductors and photovoltaic applications. In the first part, a low-cost electrodeposition (ED) method will be discussed for fabrication of high-temperature Tl-oxide-based superconductors. In the second part, electrodeposition and electroles… more
Date: January 3, 2000
Creator: Bhattacharya, R.N. & Deb, S.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Degradation Mechanisms and Dynamics of Silicon Telluride: A Guide to the Effective Fabrication and Characterization of Silicon Telluride-Based Devices

Description: Silicon telluride (Si2Te3) and many other tellurium containing compounds show emergent Raman peaks located at ~120 cm-1 and ~140 cm-1 as they age. The origin of these two emergent peaks is controversial in the literature and has been attributed to myriad causes such as the intrinsic Raman modes of the telluride materials, surface oxidation, defects, double resonances, and tellurium precipitates. The controversial nature of these peaks has led to the misidentification of highly degraded materia… more
Date: December 2023
Creator: Hathaway, Evan Allen
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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