11 Matching Results

Search Results

Advanced search parameters have been applied.
in creator/contributor: "Rozgonyi, G.A."  
Results: 1 - 11
open access

Silicon Crystal Growth and Wafer Processing for High Efficiency Solar Cells and High Mechanical Yield: Preprint

Description: Presented at the 2001 NCPV Program Review Meeting: Preliminary work on a novel process for external gettering by creating a band of silicon dioxide precipitation on top of a denuded zone via nitrogen doping is presented.
Date: October 1, 2001
Creator: Karoui, A.; Rozgonyi, G. A.; Zhang, R. & Ciszek, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Characterization of and Ti Gettering for PV Substrates: Final Subcontract Report; 28 January 1998 - 28 August 2001

Description: This report describes two project objectives: to determine optical and gettering properties of titanium and titanium oxy-nitride films, and to examine the influence of carrier recombination processes on the microwave reflection coefficient in the frequency domain such that PV materials parameters could be evaluated nondestructively. A third topic was added as the main focus, wherein we carried out a detailed characterization study of dislocated, high-purity, float-zone crystals grown at NREL. T… more
Date: June 1, 2002
Creator: Rozgonyi, G. A.; Karoui, A.; Romanowski, A. & Kordas, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Effects of Dislocations on Minority Carrier Lifetime in Dislocated Float Zone Silicon

Description: We present a correlation of Microwave Photoconductance Decay minority carrier lifetime with dislocation density in high purity Float Zone silicon. Electron Beam Induced Current (EBIC) images were carefully aligned to lifetime maps and depth profiling of individual defect electrical activity was done by varying the bias of Schottky diodes. The data presented provides a relationship between lifetime variations and EBIC contrast, based on dislocation density and impurity decoration in the near sur… more
Date: August 1, 2002
Creator: Karoui, A.; Zhang, R.; Rozgonyi, G. A. & Ciszek, T. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The effectiveness and stability of impurity/defect interactions and their impact on minority carrier lifetime. Annual subcontract report, 1 August 1990--31 July 1991

Description: This report covers the investigation and understanding of electrical activity of ``clean`` and metallic impurity decorated defects. A heterostructure containing a controlled number of deliberately introduced misfit dislocations is used as a model system to simulate a variety of defect/impurity interactions in photovoltaic materials. In addition, a noncontact laser/microwave deep-level transient spectroscopy technique is applied to characterize the minority carrier lifetime and determine the ene… more
Date: December 1, 1991
Creator: Rozgonyi, G. A.; Shimura, F.; Buczkowski, A. & Zhon, T. Q.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Thin Ni silicide formation by low temperature-induced metal atom reaction with ion implanted amorphous silicon

Description: We have extended our recent work on buried silicide formation by Ni diffusion into a buried amorphous silicon layer to the case where silicide formation is at lower temperatures on silicon substrates which have been preamorphized. The reaction of metal atoms from a 12 nm Ni film evaporated on top of a 65 nm thick surface amorphous layer formed by 35 keV Si{sup +} ion implantation has been investigated at temperature {le}400C. Rutherford Backscattering Spectrometry (RBS) with channeling, cross-s… more
Date: December 31, 1992
Creator: Erokhin, Yu.N.; Pramanick, S.; Hong, F.; Rozgonyi, G. A. & Patnaik, B. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Stress-Induced Nitrogen and Oxygen Segregation and Complexing Investigated by High Resolution Synchrotron FTIR: Preprint

Description: Nitrogen doped Czochralski (N-CZ) and Float Zone (N-FZ) silicon were measured by high resolution synchrotron Fourier Transform IR spectroscopy (HR-FTIR). The chemical complexes were analyzed in specific regions with known extended defects, i.e., denuded or precipitated regions of annealed N-CZ Si wafers, in N-FZ Si with ring defects and on ''N-Skin'' region. The absorption lines were assigned to chemical complexes previously studied by first principles calculations. In annealed N-CZ Si wafers, … more
Date: August 1, 2004
Creator: Karoui, A.; Buonassisi, T.; Sahtout Karoui, F.; Rozgonyi, G. A.; Michael, M.; Weber, E. R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Suppression of self-interstitials in silicon during ion implantation via in-situ photoexcitation

Description: The influence of in-situ photoexcitation during low temperature implantation on self-interstitial agglomeration following annealing has been investigated using transmission electron microscopy (TEM). A reduction in the level of as-implanted damage determined by RBS and TEM occurs athermally during 150 keV self-ion implantation. The damage reduction following a 300 C anneal suggests that it is mostly divacancy related. Subsequent thermal annealing at 800 C resulted in the formation of (311) rod … more
Date: February 1, 1995
Creator: Ravi, J.; Erokhin, Y.; Christensen, K.; Rozgonyi, G. A.; Patnaik, B. K. & White, C. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Charge state defect engineering of silicon during ion implantation

Description: Effects of in situ interventions which alter defect interactions during implantation, and thereby affect the final damage state, have been investigated. Specifically, we examined effects of internal electric fields and charge carrier injection on damage accumulation in Si. First, we implanted H or He ions into diode structures which were either reverse or forward biased during implantation. Second, we implanted B or Si ions into plain Si wafers while illuminating them with UV light. In each cas… more
Date: January 1997
Creator: Brown, R. A.; Ravi, J.; Erokhin, Y.; Rozgonyi, G. A. & White, C. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The influence of an in-situ electric field on H{sup +} and He{sup +} implantation induced defects in silicon

Description: The influence of in-situ electronic perturbations on defect generation during 150-keV proton implantation into biased silicon p-n junctions has been investigated. The concentration and spatial distribution of the deep traps were characterized using a modification of the double corelation deep level transient spectroscopy technique (D-DLTS). With the in-situ electric field applied, a decrease in concentration of vacancy-related, as well as H-related, traps was observed. 500 keV He{sup +} implant… more
Date: December 1, 1993
Creator: Ravi, J.; Erokhin, Y. N.; Koveshnikov, S.; Rozgonyi, G. A. & White, C. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

EBIC (electron beam induced current) contrast of clean, decorated and deuterium passivated Si(Ge) epitaxial misfit dislocations

Description: The electrical activity of as-grown and intentionally decorated misfit dislocations in an epitaxial Si/Si(Ge) heterostructure was examined using the electron beam induced current (EBIC) technique in a scanning electron microscope. Misfit dislocations, which were not visible initially, were subsequently activated either by an unknown processing contaminant or a backside metallic impurity. Passivation of these contaminated dislocations was then studied using low energy deuterium ion implantation … more
Date: January 1, 1991
Creator: Zhou, T. Q.; Buczkowski, A.; Radzimski, Z. J.; Rozgonyi, G. A. (North Carolina State Univ., Raleigh, NC (USA). Dept. of Materials Science and Engineering); Seager, C. H. & Panitz, J. (Sandia National Labs., Albuquerque, NM (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
Back to Top of Screen