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CEMS > About > Faculty > Eray Aydil

Eray Aydil

Eray Aydil

Information

Professor and Executive Officer, Ronald L. and Janet A. Christenson Chair in Renewable Energy

Phone: 612-625-8593
Email: aydil@umn.edu


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Degrees

  • B.S., Chemical Engineering, University of California at Berkeley, 1986
  • B.S., Materials Science, University of California at Berkeley, 1986
  • Ph.D., Chemical Engineering, University of Houston, 1991

Awards

  • 2009 Plasma Prize of the Plasma Science and Technology Division of the AVS
  • 2005 Fellow of the AVS
  • 2005 University of Houston Distinguished Young Engineering Alumnus
  • 1999 Peter Mark Memorial Award of the American Vacuum Society
  • 1997 Camille Dreyfus Teacher-Scholar Award
  • 1994 National Science Foundation National Young Investigator Award
  • 1993 Norman Hackerman Young Author Award of The Electrochemical Society

Research Areas

Our research focuses on renewable energy and, in particular, photovoltaics. The goal in each project is to design and develop efficient, low cost and reliable solar cells to harness solar energy. Towards this end, we conduct fundamental research on synthesis and characterization of relevant materials and devices. Currently, my students and I are working on various kinds of solar cells including:

  1. quantum-dot solar cells,
  2. dye-sensitized solar cells,
  3. copper indium gallium diselenide (CIGS) solar cells, and
  4. copper zinc tin sulfide (selenide) (CZTS) solar cells.

Quantum-dot solar cells - Quantum confinement of electrons and holes in nanometer size crystals (quantum dots or QDs), endows them with properties that may be advantageous in solar cells. The principle advantages of using QDs in solar cells include (i) the tunability of their band gap and energy levels by changing the QD size, (ii) potential for generating multiple electron-hole pairs per photon, and (iii) potential for harnessing hot electrons or holes. Moreover, QDs can be prepared in large quantities as stable colloidal solutions under mild conditions and deposited on surfaces of various planar or nanostructured substrates as thin films through inexpensive high-throughput coating processes to form photovoltaic devices. For these reasons, solar cells based on QDs may have the potential to achieve high power conversion efficiencies at low cost and are promising candidates for third generation photovoltaic devices. Specifically, we explore new types of solar cels that are based on heterojunctions between QDs and wide band gap semiconductors such as ZnO and TiO2. We study methods for QD and ZnO and TiO2 nanowire synthesis as well as methods for assembling solar cells from QDs and nanowires. We design and conduct experiments to elucidate the fundamentals of how QD-solar cells work.

Dye-sensitized solar cells - The dye-sensitized solar cell (DSSC) is one of the most promising alternatives to inorganic p-n junction based solar cells. A typical DSSC is made by depositing, on a transparent conducting oxide (TCO) substrate, a porous titanium dixide thin film that consists of crystalline nanoparticles abutted against each other and photosensitizing this film with a dye adsorbed on the surface of the nanoparticles. The pores are filled with a liquid electrolyte containing a redox couple to form a semiconductor-dye-electrolyte junction with high interfacial area. A second transparent photocathode coated with a thin platinum layer is placed across from the photosensitized semiconductor photoanode to complete the cell. During solar cell operation, the dye absorbs the photons and electrons are excited from the highest occupied molecular orbitals (HOMO) to the lowest unoccupied molecular orbitals (LUMO) of the dye. The excited electron is rapidly injected into the titanium dioxide, diffuses through the nanoporous semiconductor network and is collected at the TCO electrode. We explore improving dye-sensitized solar cell efficiency using nanowires instead of nanocrystalline particles. Nanowires provide direct collection pathways for electrons from the point of injection to the TCO electrode and have the potential to improve the charge collection efficiency of DSSCs because electron percolation through the particle network is replaced by direct electron transport to the anode.

CIGS solar cells - Copper indium gallium diselenide (CIGS) solar cells are emerging as one of the low-cost alternatives to crystalline silicon solar cells. While efficiencies exceeding 20% have been achieved on small scale in the laboratory, making large area CIGS solar cells that are resistant to environmental factors such as humidity remains a challenge. My students and I work on understanding charge transport and recombination in CIG solar cells as well as modifications of the high efficiency solar cell design and new materials to improve its reliability. We collaborate with Professor Steve Campbell in the Electrical and Computer Engineering Department.

CZTS solar cells - Thin film solar cells based on CdTe and CIGS are amongst the most promising second generation solar cell technologies. However, availability of tellurium and indium in the earth's crust may limit the terrawatt-scale production of thin film solar cells based on CdTe and CIGS. My students and I work on a new promising absorber material, Cu2ZnSnS4Se4-x (CZTS), that is like CIGS in many respects but consists of abundant and nontoxic elements. We use three different synthesis methods for depositing thin CZTS films. These include vacuum coevaporation, sulfurization of sputtered stacks of copper, zinc and tin, and deposition from colloidal dispersions of CZTS nanoparticles. We study the structural, electrical and optical properties of the CZTS films and CZTS solar cells using a suite of characterization methods.

Plasma Research - Plasma etching and deposition enables the fabrication of a wide variety of devices including microprocessors, memory devices, sensors, nozzles for inkjet printing and solar cells. We study the homogeneous and heterogeneous reactions and transport phenomena occurring in chemically reactive gas plasmas. The objective is to understand how process conditions dictate plasma properties which in turn affect the etch rate, selectivity with respect to the mask, uniformity and anisotropy. We use multiple surface and plasma characterization methods to investigate the key factors that determine the species concentrations and energy distributions in the plasma. Where necessary, we complement the experiments with modeling of the plasma and plasma-surface interactions. Recent specific projects include plasma enhanced chemical vapor deposition of carbon nanotubes and the effect of nanoparticles on the plasma properties.

Selected Publications

  • B. S. Tosun, B. D. Chernomordik, A. A. Gunawan, B. Williams, K. A. Mkhoyan, L. F. Francis and E. S. Aydil, “Cu2ZnSnS4 Nanocrystal Dispersions in Polar Liquids,” Chem. Comm. 49, 3549-3551 (2013).
  • X. Zhang, M. Manno, A. Baruth, M. Johnson, E. S. Aydil, and C. Leighton, “Crossover From Nanoscopic Intergranular Hopping to Conventional Charge Transport in Pyrite Thin Films,” ACS Nano 7, 2781-2789 (2013).
  • N. Rastgar, D. J. Rowe, R. J. Anthony, B. A. Merritt, U. R. Kortshagen and E. S. Aydil, “Effects of Water Adsorption and Surface Oxidation on the Electrical Conductivity of Silicon Nanocrystal Films,” J. Phys. Chem. C 117, 4211-4218 (2013).
  • D. J. Norris and E. S. Aydil, “Getting Moore from Solar Cells,” Science 338, 625-626 (2012).
  • A. Baruth, M. Manno, D. Narasimhan, A. Shankar, X. Zhang, M. Johnson, E. S. Aydil, and C. Leighton, “Reactive Sputter Deposition of Pyrite Structure Transition Metal Disulfide Thin Films: Microstructure, Transport and Magnetism,” J. Appl. Phys. 112, 054328 (2012).
  • B. Liu, A. Khare and E. S. Aydil, “Synthesis of Single-Crystalline Anatase Nanorods and Nanoflakes on Transparent Conducting Substrates,” Chem. Commun. 45, 8565-8567 (2012).
  • B. S. Tosun, C. Pettit, S. A. Campbell and E. S. Aydil, “Structure and Composition of ZnxCd1-xS Films Synthesized through Chemical Bath Deposition,” ACS Appl. Mater. Interfaces 4, 3676-3684 (2012).
  • A. Khare, B. Himmetoglu, M. Cococcioni and E. S. Aydil, “First Principles Calculation of the Electronic Properties and Lattice Dynamics of Cu2ZnSn(S1−xSex)4,” J. Appl. Phys. 111, 123704 (2012).
  • A. Khare, B. Himmetoglu, M. Johnson, D. J. Norris, M. Cococcioni and E. S. Aydil, “Calculation of the Lattice Dynamics and Raman Spectra of Copper Zinc Tin Chalcogenides and Comparison to Experiments,” J. Appl. Phys. 111, 083707 (2012).
  • B. S. Tosun, R. K. Feist, S. A. Campbell and E. S. Aydil, “Tin Dioxide as an Alternative Window Layer for Improving the Damp-Heat Stability of Copper indium Gallium Diselenide Solar Cells,” J. Vac. Sci. Technol. A 30, 04D101 (2012).
  • B. S. Tosun, R. K. Feist, A. Gunawan, K. A. Mkhoyan, S. A. Campbell and E. S. Aydil, “Improving the Damp-Heat Stability of Copper Indium Gallium Diselenide Solar Cells with a Semicrystalline Tin Dioxide Overlayer,” Solar Energy Materials and Solar Cells 101, 270-276 (2012).
  • B. S. Tosun, R. K. Feist, A. Gunawan, K. A. Mkhoyan, S. A. Campbell and E. S. Aydil, “Sputter Deposition of Semicrystalline Tin Dioxide Films,” Thin Solid Films 520, 2554–2561 (2012).
  • B. Liu, A. Khare and E. S. Aydil, “TiO2-B/Anatase Core-Shell Heterojunction Nanowires for Photocatalysis,” ACS Appl. Mater. Interfaces 3, 4444-4450 (2011).
  • A. Khare, A. W. Wills, L. M. Ammerman, D. J. Norris and E. S. Aydil, “Size Control and Quantum Confinement in Cu2ZnSnS4 Nanocrystals,” Chem. Commun. 47, 11721-11723 (2011).
  • B. Liu and E. S. Aydil, “Anatase TiO2 Films with Reactive {001} Facets on Transparent Conductive Substrate,” Chem. Commun. 47, 9507-9509 (2011).
  • B. Liu and E. S. Aydil, “Layered Mesoporous Nanostructures for Enhanced Light Harvesting in Dye-Sensitized Solar Cells,” Journal of Renewable and Sustainable Energy 3, 043106 (2011).
  • A.-J Cheng, M. Manno, A. Khare, C. Leighton, S. Campbell and E. S. Aydil, “Imaging and Phase Identification of Cu2ZnSnS4 Thin Films Using Confocal Raman Spectroscopy,” J. Vac. Sci. Technol. A 29, 051203 (2011).
  • M. J. Behr, K. A. Mkhoyan, and E. S. Aydil, “Carbon Diffusion from Methane into Walls of Carbon Nanotube through Structurally and Compositionally Modified Iron Catalyst,” Microscopy and Microanalysis 17, 582-586 (2011).
  • S. H. Jeong, S. H. Song, K. Nagaich, S. A. Campbell, E. S. Aydil, “An Analysis of Temperature Dependent Current–Voltage Characteristics of Cu2O–ZnO Heterojunction Solar Cells,” Thin Solid Films 519, 6613-6619 (2011).
  • C. A. Wolden, J. Kurtin, J. B. Baxter, I. Repins, S. E. Shaheen, J. T. Torvik, A. A. Rockett, V. M. Fthenakis and E. S. Aydil, “Photovoltaic Manufacturing: Present Status, Future Prospects and Research Needs,” J. Vac. Sci. Technol. A 29, 030801 (2011).
  • N. Araki, E. S. Aydil and K. Dorfman, “Collision of a Long DNA molecule with an Isolated Nanowire,” Electrophoresis 31, 3675-3680 (2010).
  • M. J. Behr, E. A. Gaulding, A. K. Mkhoyan and E. S. Aydil, “Hydrogen Etching and Cutting of Multiwall Carbon Nanotubes,” J. Vac. Sci. Technol. B 28 1187-1194 (2010).
  • S. Jeong and E. S. Aydil, “Structural and Electrical Properties of Cu2O Thin Films Deposited on ZnO by Metal Organic Chemical Vapor Deposition,” J. Vac. Sci. Technol. A 28, 1338-1343 (2010).
  • M. J. Behr, A. K. Mkhoyan and E. S. Aydil, “Orientation and Morphological Evolution of Catalyst Nanoparticles During Carbon Nanotube Growth,” ACS Nano 4, 5087-5094 (2010).
  • M. J. Behr, E. A. Gaulding, A. K. Mkhoyan and E. S. Aydil, “Effect of Hydrogen on Catalyst Nanoparticles in Carbon Nanotube Growth,” J. Appl. Phys. 108, 053303 (2010).
  • M. J. Behr, A. K. Mkhoyan and E. S. Aydil, “Catalyst Rotation, Twisting, and Bending During Multiwall Carbon Nanotube Growth,” Carbon 48, 3840-3845 (2010).
  • B. Liu, D. Deng, J. Y. Lee and E. S. Aydil, “Oriented Single-Crystalline TiO2 Nanowires on Titanium Foil for Lithium Ion Batteries,” J. Mater. Res. 25, 1588- 1594 (2010).
  • W. A. Tisdale, K. J. Williams, B. C. Timp, D. J. Norris, E. S. Aydil and X.-Y. Zhu, “Hot Electron Transfer from Semiconductor Nanocrystals,” Science 328, 1543-1547 (2010).
  • K. S. Leschkies, M. S. Kang, E. S. Aydil and D. J. Norris, “Influence of Atmospheric Gases on the Electrical Properties of PbSe Quantum-Dot Films,” J. Phys. Chem. C 114, 9988-9996 (2010).
  • K. S. Leschkies, A. G. Jacobs, D. J. Norris, and E. S. Aydil, “Nanowire-Quantum-Dot Solar Cells and the Influence of Nanowire Length on the Charge Collection Efficiency,” Appl. Phys. Lett. 95, 193103 (2009).
  • K. S. Leschkies, T. J. Beatty, M. S. Kang, D. J. Norris, and E. S. Aydil, “Solar Cells Based on Junctions Between Colloidal PbSe Nanocrystals and Thin ZnO Films,” ACS Nano 11, 3638-3648 (2009).
  • A. R. Muniz, T. Singh, E. S. Aydil, and D. Maroudas, “Analysis of Diamond Nanocrystal Formation from Multi-walled Carbon Nanotubes,” Phys. Rev. B 80, 144105 (2009).
  • E. Enache-Pommer, B. Liu and E. S. Aydil, “Electron Transport and Recombination in Dye-Sensitized Solar Cells Made from Single Crystal Rutile TiO2 Nanowires,” Phys. Chem. Chem. Phys. 11, 9648-9652 (2009).
  • S. Jeong and E. S. Aydil, “Heteroepitaxial Growth of Cu2O Thin Film on ZnO by Metal Organic Chemical Vapor Deposition,” J. Cryst. Growth 311, 4188-4192 (2009).
  • K. J. Williams, W. A. Tisdale, K. S. Leschkies, G. Haugstad, D. J. Norris, E. S. Aydil and X.-Y. Zhu, “Strong Electronic Coupling in Two-Dimensional Assemblies of Colloidal PbSe Quantum Dots,” ACS Nano 3, 1532-1538 (2009).
  • T. Singh, M. J. Behr, E. S. Aydil and D. Maroudas, “First-Principles Theoretical Analysis of Pure and Hydrogenated Crystalline Carbon Phases and Nanostructures,” Chem. Phys. Lett. 474, 168-174 (2009).
  • J. E. Boercker, J. B. Schmidt and E. S. Aydil, “Transport Limited Growth of Zinc Oxide Nanowires,” Cryst. Growth Des. 9, 2783-2789 (2009).
  • B. Liu and E. S. Aydil, “Growth of Oriented Single-Crystalline Rutile TiO2 Nanorods on Transparent Conducting Substrates for Dye-Sensitized Solar Cells,” J. Am. Chem. Soc. 131, 3985-3990 (2009).
  • J. B. Baxter and E. S. Aydil, “Metalorganic Chemical Vapor Deposition of ZnO Nanowires from Zinc Acetylacetonate and oxygen,” J. Electrochem. Soc. 156, H52-H58 (2009).
  • B. Liu, J. E. Boercker, and E. S. Aydil, “Oriented Single-Crystalline Anatase TiO2 Nanowires,” Nanotechnology 19, 505604 (2008).
  • W. A. Tisdale, M. Muntwiler, D. J. Norris, E. S. Aydil and X.-Y Zhu, “Electron Dynamics at the ZnO Surface,” J. Phys. Chem. C 112, 14682-14692 (2008).
  • B. Carlson, K. S. Leschkies, E. S. Aydil and X.-Y Zhu, “Valence Band Alignment at CdSe Quantum Dot and ZnO (101-0) Interfaces,” J. Phys. Chem. C 112, 8419-8423 (2008).
  • J. E. Boercker, E. Enache-Pommer, and E. S. Aydil, “Growth Mechanism of TiO2 Nanowires for Dye-Sensitized Solar Cells,” Nanotechnology 19, 095604 (2008).
  • R. C. Mani, I. Pavel, and E. S. Aydil, "Deposition of Nanocrystalline Silicon Films at Room Temperature," J. Appl. Phys. 102, 043305 (2007).
  • E. Enache-Pommer, J. E. Boercker and E. S. Aydil, “Electron Transport and Recombination in Polycrystalline TiO2 Nanowire Dye-Sensitized Solar Cells,” Appl. Phys. Lett. 91, 123116 (2007).
  • K. S. Leschkies, R. Divakar, J. Basu, E. Enache-Pommer, J. E. Boercker, C. B. Carter, U. R. Kortshagen, D. J. Norris, and E. S. Aydil, “Photosensitization of ZnO Nanowires with CdSe Quantum Dots for Photovoltaic Devices,” Nano Lett. 7, 1793-1798 (2007).
  • J. R. Belen, S. Gomez, M. Kiehlbauch and E. S. Aydil, “In Situ Measurement of the Ion Incidence Angle Dependence of the Ion-Enhanced Etching Yield in Plasma Reactors,” J. Vac. Sci. Technol. A 24, 2176-2186 (2006).
  • M. S. Valipa, S. Sriraman, E. S. Aydil, and D. Maroudas, “Hydrogen-Induced Crystallization of Amorphous Silicon Thin Films. II. Mechanisms and Energetics of Hydrogen Insertion into Si-Si Bonds,” J. Appl. Phys. 100, 053515 (2006).
  • S. Sriraman, M. S. Valipa, E. S. Aydil, and D. Maroudas, “Hydrogen-Induced Crystallization of Amorphous Silicon Thin Films. I. Simulation and Analysis of Film Post Growth Treatment with H2 Plasmas,” J. Appl. Phys. 100, 053514 (2006).
  • J. B. Baxter, A. M. Walker, K. van Ommering, and E. S. Aydil, “Synthesis and Characterization of ZnO Nanowires and their Integration into Dye Sensitized Solar Cells,” Nanotechnology 17, S304 (2006).
  • J. R. Belen, S. Gomez, M. Kiehlbauch and E. S. Aydil, “Feature-scale Model of Si etching in SF6/O2/HBr Plasma and Comparison with Experiments,” J. Vac. Sci. Technol. A 24, 350 (2006).
  • J. B. Baxter and E. S. Aydil, “Dye Sensitized Solar Cells Based on Semiconductor Morphologies with ZnO Nanowires,” Sol. Energ. Mat. Sol. C. 90, 607 (2006).
  • M. S. Valipa, S. Sriraman, E. S. Aydil, and D. Maroudas, “Atomic-Scale Analysis of Fundamental Mechanisms of Surface Valley Filling During Plasma Deposition of Amorphous Silicon Thin Films,” Surf. Sci. 574, 123-143 (2005).
  • S. Agarwal, M. S. Valipa, B. Hoex, M. C. M. van de Sanden, D. Maroudas and E. S. Aydil, “Interaction of SiH3 Radicals with an Amorphous Deuterated (Hydrogenated) Silicon Surface,” Surf. Sci. 598, 35-44 (2005).
  • M. S. Valipa, T. Bakos, E. S. Aydil, and D. Maroudas, “Surface Smoothening Mechanism of Amorphous Silicon Thin Films,” Phys. Rev. Lett. 95, 216102 (2005).
  • S. Gomez, J. R. Belen, M. Kiehlbauch, and E. S. Aydil, “Etching of High Aspect Ratio Features in Si using SF6/O2/HBr and SF6/O2/Cl2 Plasma,” J. Vac. Sci. Technol. A 23, 1592 (2005).
  • T. Bakos, M. Valipa, E. S. Aydil, and D. Maroudas, “Temperature Dependence of Precursor-Surface Interactions in Plasma Deposition of Silicon Thin Films,” Chem. Phys. Lett. 414, 61-65 (2005).
  • J. R. Belen, S. Gomez, D. Cooperberg, M. Kiehlbauch and E. S. Aydil, “Feature-Scale Model of Si Etching in SF6/O2 Plasma and Comparison with Experiments,” J. Vac. Sci. Technol. A 23, 1430-1439 (2005).
  • M. Valipa, E. S. Aydil, and D. Maroudas, “Visualizing the Evolution of Surface Morphology and Surface Bond Strain During Plasma Deposition of Amorphous Silicon Thin Films,” IEEE T. Plasma Sci. 33, 228-229 (2005).
  • J. B. Baxter and E. S. Aydil, “Nanowire-Based Dye-Sensitized Solar Cells,” Appl. Phys. Lett. 86, 053114 (2005).
  • C. A. Wolden, T. M. Barnes, J. B. Baxter, and E. S. Aydil, “Infrared detection of Hydrogen-Generated Free Carriers in Polycrystalline ZnO Thin Films,” J. Appl. Phys. 97, 043522 (2005).
  • J. B. Baxter and E. S. Aydil, “Epitaxial Growth of ZnO Nanowires on a- and c-plane Sapphire,” Journal of Crystal Growth 274, 407 (2005).
  • M. S. Valipa, E. S. Aydil, and D. Maroudas, “Atomistic Calculation of the SiH3 Surface Reactivity During Plasma Deposition of Amorphous Silicon Thin Films,” Surf. Sci. Lett. 572, L339-L347 (2005).
  • R. J. Belen, S. Gomez, M. Kiehlbauch, D. Cooperberg and E. S. Aydil, “Feature-Scale Model of Si Etching in SF6 Plasma and Comparison with Experiments,” J. Vac. Sci. Technol. A 23, 99 (2005).
  • S. Gomez, J. R. Belen, M. Kiehlbauch, and E. S. Aydil, “Etching of High Aspect Ratio Structures in Si Using SF6/O2 Plasma,” J. Vac. Sci. Technol. A 22, 606 (2004).
  • S. Agarwal, G. W. W. Quax, M. C. M. van de Sanden, D. Maroudas and E. S. Aydil, “Measurement of Absolute Radical Densities in a Plasma Using Modulated Beam Line-of-Sight Threshold Ionization Mass Spectrometry,” J. Vac. Sci. Technol. A 22, 71-81 (2004).
  • S. Sriraman, E. S. Aydil, and D. Maroudas, “Growth and Characterization of a-Si:H Thin Films from SiH2 Radical Precursor: An Atomic Scale Analysis,” J. Appl. Phys. 95, 1792-1805 (2004).
  • S. Agarwal, B. Hoex, M. C. M. van de Sanden, D. Maroudas, and E. S. Aydil, “Hydrogen in Si-Si Bond-Center and Platelet-Like Configurations in Amorphous Hydrogenated Silicon,” J. Vac. Sci. Technol. B 22, 2719-2726 (2004).
  • J. B. Baxter, F. Wu, and E. S. Aydil, “Growth Mechanism and Characterization of Zinc Oxide Hexagonal Columns,” Appl. Phys. Lett. 83, 3797 (2003).
  • S. Agarwal. B. Hoex, M. C. M. van de Sanden, D. Maroudas and E. S. Aydil “Absolute densities of N and Excited N2 in an N2 Plasma,” Appl. Phys. Lett. 83, 4918-4920 (2003).
  • S. Sriraman, P. Mahalingam, E. S. Aydil, D. Maroudas, “Mechanism and Energetics of Dimerization of SiH2 Radicals on H-Terminated Si (001)-(2×1) Surfaces,” Surf. Sci. Lett. 540, L623-L630 (2003).
  • T. W. Kim and E. S. Aydil, “Experimental and Theoretical Study of Two-Dimensional Ion Flux Uniformity at the Wafer Plane in Inductively Coupled Plasmas,” IEEE T. Plasma Sci. 31, 614 (2003).
  • T. W. Kim and E. S. Aydil, “Spatial and Temporal Variation of Ion Flux in Presence of an Instability in Inductively Coupled SF6 Plasmas,” Plasma Sources Sci. T. 12, 148 (2003).
  • T. W. Kim and E. S. Aydil, “Effects of Chamber Wall Conditions on Cl Concentration and Si Etch rate Uniformity in Plasma Etching Reactors,” J. Electrochem. Soc. 150, 418 (2003).
  • D. C. Marra, W. M. M. Kessels, M. C. M. Van de Sanden, K. Kashefizadeh, and E. S. Aydil, “In Situ Infrared Study of the Role of Ion Flux and Substrate Temperature on a-Si:H Surface Composition,” Surf. Sci. 530, 1-16 (2003).
  • S. J. Ullal. T. W. Kim, V. Vahedi, and E. S. Aydil, “Relation Between the Ion Flux, Gas Phase Composition, and Wall Conditions in Chlorine Plasma Etching of Silicon,” J. Vac. Sci. Technol. A 21, 589 (2003).
  • A. Takano and E. S. Aydil, “Incorporation of Cl into Hydrogenated Amorphous Silicon without Optical Band Gap Widening,” Jpn. J. Appl. Phys. 41, L1357 (2002).
  • T. W. Kim and E. S. Aydil, “Two Dimensional Ion Flux Distributions in Inductively coupled Plasmas: Effect of Adding Electronegative Gases to Ar,” J. Appl. Phys. 92, 6444 (2002).
  • S. Agarwal, A. Takano, M. C. M. Van de Sanden, D. Maroudas, and E. S. Aydil, “Abstraction of Atomic Hydrogen by Atomic Deuterium from an Amorphous Hydrogenated Silicon Surface,” J. Chem. Phys. 117, 10805-10816 (2002).
  • S. J. Ullal, H. Singh, J. Daugherty, V. Vahedi, E. S. Aydil, “Formation and Removal of Composite Halogenated Silicon Oxide and Fluorocarbon Films Deposited on Chamber Walls During Plasma Etching of Multiple Film Stacks,” J. Vac. Sci. Technol. B 20, 1939 (2002).
  • S. Sriraman, E. S. Aydil, and D. Maroudas, “Atomic-Scale Analysis of Deposition and Characterization of a-Si:H Thin Films Grown from SiH Radical Precursor,” J. Appl. Phys. 92, 842-852 (2002).
  • T. W. Kim, S. J. Ullal, V. Vahedi, and E. S. Aydil, “An On-Wafer Probe Array for Measuring Two-Dimensional Ion Flux Distributions in Plasma Reactors,” Rev. Sci. Instrum. 73, 3494 (2002).
  • S. Sriraman, S. Agarwal, E. S. Aydil, and D. Maroudas, “Mechanism of Hydrogen Induced Crystallization of Amorphous Silicon,” Nature 418, 62-65 (2002).
  • S. Agarwal, S. Sriraman, E. S. Aydil, and D. Maroudas, “Mechanism and Activation Energy Barrier for H Abstraction by H(D) from a-Si:H Surfaces,” Surface Science 515, L469-L474 (2002).
  • S. J. Ullal, H. Singh, V. Vahedi, and E. S. Aydil, “Deposition of Silicon Oxychloride Films on Chamber Walls During Cl2/O2 Plasma Etching of Si,” J. Vac. Sci. Technol. A 20, 499 (2002).
  • S. J. Ullal, H. Singh, J. Daugherty, V. Vahedi, and E. S. Aydil, “Maintaining Reproducible Plasma Reactor Wall Conditions: SF6 Plasma Cleaning of Films Deposited on Chamber Walls During Cl2/O2 Plasma Etching of Si,” J. Vac. Sci. Technol. A 20, 1195 (2002).
  • S. J. Ullal, H. Singh, V. Vahedi, and E. S. Aydil, “Deposition of Silicon Oxychloride Films on Chamber Walls During Cl2/O2 Plasma Etching of Si,” J. Vac. Sci. Technol. A 20, 499 (2002).
  • S. J. Ullal, H. Singh, J. Daugherty, V. Vahedi, and E. S. Aydil, “Maintaining Reproducible Plasma Reactor Wall Conditions: SF6 Plasma Cleaning of Films Deposited on Chamber Walls During Cl2/O2 Plasma Etching of Si,” J. Vac. Sci. Technol. A 20, 1195 (2002).
  • T. W. Kim and E. S. Aydil, “Spatial and Temporal Variation of the Ion Flux Impinging on the Wafer Surface in Presence of a Plasma Instability,” IEEE Transactions on Plasma Science 30, 120 (2002).
  • S. Sriraman, E. S. Aydil and D. Maroudas, “Visualizing the Evolution of Surface Bond Straining During Radical-Surface Interactions in Plasma Deposition Processes,” IEEE Transactions on Plasma Science 30, 112-113 (2002).
  • S. J. Ullal, A. R. Godfrey, E. A. Edelberg, L. B. Braly, V. Vahedi, and E. S. Aydil, “Effect of Chamber Wall Conditions on Cl and Cl2 Concentrations in an Inductively Coupled Plasma reactor,” J. Vac. Sci. Technol. A 20, 43 (2002).
  • W. M. M. Kessels, D. C. Marra, M. C. M. Van de Sanden, and E. S. Aydil, “In Situ Probing of Surface Hydrides on Hydrogenated Amorphous Silicon Using Attenuated Total Reflection Infrared Spectroscopy,” J. Vac. Sci. Technol. A 20, 781-789 (2002).
  • S. Ramalingam, E. S. Aydil, and D. Maroudas, “Molecular Dynamics Study of the Interactions of Small Thermal and Energetic Clusters with Crystalline and Amorphous Silicon Surfaces,” J. Vac. Sci. Technol. B 19, 634-644 (2001).
  • D. Y. Takamoto, E. S. Aydil, J. A. Zasadzinski, A. T. Ivanova, D. K. Schwartz, T. Yang, and P. S. Cremer, “Nanoscale Reorganization in Langmuir Blodgett Films,” Science 293, 1292 (2001).
  • S. P. Walch, S. Ramalingam, S. Sriraman, E. S. Aydil, and D. Maroudas, “Mechanism and Energetics of SiH3 Adsorption on the Pristine Si(001)- (2×1) Surface,” Chem. Phys. Lett. 344, 249-255 (2001).
  • A. R. Godfrey, S. J. Ullal, L. B. Braly, E. A. Edelberg, V. Vahedi, and E. S. Aydil, “A New Diagnostic Method for Monitoring Plasma Reactor Walls: Multiple Total Internal Reflection Fourier Transform Infrared Surface Probe,” Rev. Sci. Instrum. 72, 3260 (2001).
  • S. Ramalingam, S. Sriraman, E. S. Aydil, and D. Maroudas, “Evolution, Structure, Morphology and Reactivity of Hydrogenated Amorphous Silicon Surfaces Grown by Molecular-Dynamics Simulation,” Appl. Phys. Lett. 78, 2685-2687 (2001).
  • W. M. M. Kessels, A. H. M. Smets, D. C. Marra, E. S. Aydil, D. C. Schram, and, M. C. M. van de Sanden, “On the Growth Mechanism of Hydrogenated Amorphous Silicon,” Thin Solid Films 383, 154-160 (2001).
  • S. P. Walch, S. Ramalingam, E. S. Aydil, and D. Maroudas, “Mechanism and Energetics of Dissociative Adsorption of SiH3 on the Hydrogen Terminated Si (001)-(2×1) Surface,” Chem. Phys. Lett. 329, 304-310 (2000).
  • D. C. Marra, E. S. Aydil, S. J. Joo, E. Yoon, and V. I. Srdanov, “Angle-Dependent Photoluminescence Spectra of Hydrogenated Amorphous Silicon Thin Films,” Appl. Phys. Lett. 77, 3346 (2000).
  • S. Sriraman, S. Ramalingam, E. S. Aydil, and D. Maroudas, “Abstraction of Hydrogen by SiH Radicals from Hydrogenated Amorphous Silicon Surfaces,” Surf. Sci. Lett. 459, L475-L481 (2000).
  • N. A. Alcantar, E. S. Aydil, J. N. Israelachvili, “Polyethylene Glycol Coated Biocompatible Surfaces,” J. Biomed. Mater. Res. 51, 343 (2000).
  • S. Ramalingam, P. Mahalingam, E. S. Aydil, and D. Maroudas, “Theoretical Study of the Interactions of SiH2 Radicals with Silicon Surfaces,” J. Appl. Phys. 86, 5497-5508 (1999).
  • E. A. Edelberg and E. S. Aydil, “Modeling of the Sheath and the Energy Distribution of Ions Bombarding rf-Biased Substrates in High Density Plasma Reactors and Comparison to Experimental Measurements,” J. Appl. Phys. 86, 4799-4812 (1999).
  • E. A. Edelberg, A. J. Perry, N. Benjamin, and E. S. Aydil, “Compact Floating Ion Energy Analyzer for Measuring Distributions of Ions Bombarding Radio-Frequency Biased Electrode Surfaces,” Rev. Sci. Instrum. 70, 2689 (1999).
  • S. Ramalingam, D. Maroudas, and E. S. Aydil, “Atomistic Simulation Study of the Interactions of SiH3 Radicals with Silicon Surfaces,” J. Appl. Phys. 86, 2872-2888 (1999).
  • B. F. Hanyaloglu, A. Aydinli, M. Oye, and E. S. Aydil, “Plasma Enhanced Chemical Vapor Deposition of Low Dielectric Constant Parylene-F Intermetal Dielectric Films,” Appl. Phys. Lett. 74, 606 (1999).
  • E. A. Edelberg, A. Perry, N. Benjamin, and E. S. Aydil, “Energy Distribution of Ions Bombarding Biased Electrodes in High Density Plasma Reactors,” J. Vac. Sci. Technol. A 17, 506-516 (1999).
  • S. Ramalingam, D. Maroudas, and E. S. Aydil, “Visualizing Radical-Surface Interactions in Plasma Deposition Processes: Reactivity of SiH3 Radicals with Si Surfaces,” IEEE Transactions on Plasma Science 27, 104-105 (1999).
  • S. Ramalingam, D. Maroudas, E. S. Aydil, and S. P. Walch, “Abstraction of Hydrogen by SiH3 from Hydrogen Terminated Si(001)-(2x1) Surfaces,” Surface Science Letters 418, L8-L13 (1998).
  • D. C. Marra, E. A. Edelberg, R. L. Naone, and E. S. Aydil, “Silicon Hydride Composition of Plasma-Deposited Hydrogenated Amorphous and Nanocrystalline Silicon Films and Surfaces,” J. Vac. Sci. Technol. A 16, 3199-3210 (1998).
  • S. Ramalingam, D. Maroudas, and E. S. Aydil, “Interaction of SiH Radicals with Silicon Surfaces: An Atomic Scale Simulation Study,” J. Appl. Phys. 84, 3895-3911 (1998).
  • B. F. Hanyaloglu and E. S. Aydil, “Low temperature Plasma Deposition of Silicon Nitride from Silane and Nitrogen Plasmas,” J. Vac. Sci. Technol. A 16, 2794 (1998).
  • D. C. Marra, E. A. Edelberg, R. L. Naone, and E. S. Aydil, “Effect of H2 Dilution on the Surface Composition of Plasma-Deposited Silicon Films from SiH4,” Appl. Surf. Sci. 133, 148-151 (1998).
  • E. S. Aydil, B. O. M. Quiniou, J. T. C. Lee, J. A. Gregus, R. A. Gottscho, “Incidence Angle Distributions of Ions Bombarding Grounded Surfaces in High Density Plasma Reactors,” Materials Science in Semiconductor Processing 1, 75 (1998).
  • S. M. Han and E. S. Aydil, “Reasons for Lower Dielectric Constant of Fluorinated Silicon Dioxide Films,” J. Appl. Phys. 83, 2172 (1998).
  • S. Ramalingam, D. Maroudas, and E. S. Aydil, “Atomistic Simulation of SiH Interactions with Silicon Surfaces During Deposition from Silane Containing Plasmas,” Appl. Phys. Lett. 72, 578-580 (1998).
  • E. Meeks, R. S. Larson, P. Ho, C. Apblett, S. M. Han, E. Edelberg, and E. S. Aydil, “Modeling of SiO2 Deposition in High Density Plasma Reactors and Comparisons of Model Predictions with Experimental Measurements,” J. Vac. Sci. Technol. A 16, 544 (1998).
  • S. M. Han and E. S. Aydil, “Structure and Chemical Composition of Fluorinated SiO2 Films Deposited Using SiF4/O2 Plasmas,” J. Vac. Sci. Technol. A 15, 2893 (1997).
  • S. M. Han and E. S. Aydil, “Detection of Combinative Infrared Absorption Bands in Thin Silicon Dioxide Films,” Appl. Phys. Lett. 70, 3269 (1997).
  • D. C. Marra and E. S. Aydil, “Effect of H2 Addition on Surface Reactions During CF4/H2 Plasma Etching of Silicon and Silicon Dioxide Films,” J. Vac. Sci. Technol. A 15, 2508 (1997).
  • S. M. Han and E. S. Aydil, “Silanol Concentration Depth Profiling During Plasma Deposition of SiO2 using Multiple Internal Reflection Infrared Spectroscopy,” J. Electrochem. Soc. 144, 3963 (1997).
  • E. S. Aydil and R. A. Gottscho, “Probing Plasma/Surface Interactions,” Solid State Technology 40 (10), 181 (October, 1997).
  • E. Edelberg, S. Bergh, R. Naone, M. Hall, and E. S. Aydil, “Luminescence from Plasma Deposited Silicon Films,” J. Appl. Phys. 81, 2410 (1997).
  • S. M. Han and E. S. Aydil, “Plasma and Surface Diagnostics During Plasma Enhanced Chemical Vapor Deposition of SiO2 from SiH4/O2/Ar Discharges,” Thin Solid Films 291, 427 (1996).
  • D. Tretheway, and E. S. Aydil, “Modeling of Heat Transport and Wafer Heating Effects during Plasma Etching” J. Electrochem. Soc. 143, 3674 (1996).
  • E. Edelberg, S. Bergh, R. Naone, M. Hall, and E. S. Aydil, “Visible Luminescence from Nanocrystalline Silicon Films Produced by Plasma Enhanced Chemical Vapor Deposition,” Appl. Phys. Lett. 68, 1415 (1996).
  • S. M. Han and E. S. Aydil, “Study of Surface Reactions During Plasma Enhanced Chemical Vapor Deposition of SiO2 from SiH4, O2 and Ar Plasma,” J. Vac. Sci Technol. A 14, 2062 (1996).
  • S. C. Deshmukh and E. S. Aydil, "An Investigation of Low Temperature SiO2 Plasma Enhanced Chemical Vapor Deposition," J. Vac. Sci. Technol. B 14, 738 (1996).
  • S. C. Deshmukh and E. S. Aydil, "Investigation of SiO2 Plasma Enhanced Chemical Vapor Deposition through Tetraethoxysilane Using Attenuated Total Reflection Fourier Transform Infrared Spectroscopy," J. Vac. Sci. Technol. A 13, 2355 (1995).
  • E. S. Aydil, Z. H. Zhou, R. A. Gottscho, and Y. J. Chabal, "Real Time In Situ monitoring of Surfaces During Glow Discharge Processing: NH3 and H2 Plasma Passivation of GaAs," J. Vac. Sci. Technol. B 13, 258 (1995).
  • S. C. Deshmukh and E. S. Aydil, "Low Temperature Plasma Enhanced Chemical Vapor Deposition of SiO2," Appl. Phys. Lett. 65, 3185 (1994).
  • E. S. Aydil, R. A. Gottscho, and Y. J. Chabal, "Real Time Monitoring of Surface Chemistry During Plasma Processing," Pure and Applied Chemistry 66, 1381 (1994).
  • E. S. Aydil, J. A. Gregus, and R. A. Gottscho, "Electron Cyclotron Resonance Plasma Reactor for Cryogenic Etching," Rev. Sci. Instrum. 64, 3572-3584 (1993).
  • M. A. Jarnyk, J. A. Gregus, E. S. Aydil, and R. A. Gottscho, "Control of an Unstable Electron Cyclotron Resonance Plasma," Appl. Phys. Lett. 62, 2039 (1993).
  • E. S. Aydil, J. A. Gregus, and R. A. Gottscho, "Multiple Steady States in Electron Cyclotron Resonance Plasma Reactors," J. Vac. Sci. Technol. A 11, 2883 (1993).
  • Z. Zhou, E. S. Aydil, R. A. Gottscho, Y. J. Chabal, and R. Reif, "Real Time, In Situ Monitoring of Room Temperature Silicon Surface Cleaning Using Hydrogen and Ammonia Plasmas," J. Electrochem. Soc. 140, 3316 (1993).
  • E. S. Aydil, Z. Zhou, K. P. Giapis, Y. J. Chabal, J. A. Gregus, and R. A. Gottscho, "Real Time, In Situ Monitoring of Surface Reactions During Plasma Passivation of GaAs," Appl. Phys. Lett. 62, 3156 (1993).
  • E. S. Aydil, K. P. Giapis, R. A. Gottscho, V. M. Donnelly, and E. Yoon, "Ammonia Plasma Passivation of GaAs in Downstream Microwave and RF Parallel Plate Plasma Reactors," J. Vac. Sci. Technol. B 11, 195 (1993).
  • E. S. Aydil and D. J. Economou, "Modeling of Plasma Etching Reactors Including Wafer Heating Effects," J. Electrochem. Soc. 140, 1471 (1993).
  • E. S. Aydil and D. J. Economou, "Theoretical and Experimental Investigations of Chlorine RF Glow Discharges: II. Experimental," J. Electrochem. Soc. 139, 1406 (1992).
  • E. S. Aydil and D. J. Economou, "Theoretical and Experimental Investigations of Chlorine RF Glow Discharges: I. Theoretical," J. Electrochem. Soc. 139, 1396 (1992).
  • D. Economou, E. S. Aydil and G. Barna, "In Situ Monitoring of Etching Uniformity in Plasma Reactors," Solid State Technology 34 (4), 107 (April, 1991).
  • E. S. Aydil and D. J. Economou, "Multiple Steady States in a Radio Frequency Chlorine Glow Discharge," J. Appl. Phys. 69, 109 (1991).