Browsing by Keywords "Epitaxial growth"

Now showing items 1-20 of 20

    • Ab initio temperature dependent studies of the homoepitaxial growth on Si(0 0 1) surface 

      Dağ, S.; Çıracı, Salim; Kılıç, Ç.; Fong, C. Y. (2001)
      We performed ab initio zero temperature and finite temperature molecular dynamics calculations to investigate the homoepitaxial growth on the Si(0 0 1) surface. How do the deposited atoms (adatoms) form addimers and how ...

    • Atomic scale investigation of clean and epi-grown Si(001) surfaces using scanning tunneling microscopy 

      Özer, H. Özgür (Bilkent University, 1996)
      In this thesis, clean and epi-grown Si(001)(2x1)surfaces are analyzed by Scanning Tunneling Microscopy (STM). The STM and Ultra High Vacuum System (UHV) in which the microscope is installed, are described. A brief history ...

    • Controlled growth and characterization of epitaxially-laterally-overgrown InGaN/GaN quantum heterostructures 

      Sarı, Emre; Akyuz, Özgün; Choi, E. -G.; Lee I.-H.; Baek J.H.; Demir, Hilmi Volkan (IEEE, 2010)
      Crystal material quality is fundamentally important for optoelectronic devices including laser diodes and light emitting diodes. To this end epitaxial lateral overgrowth (ELO) has proven to be a powerful technique for ...

    • Defect reduction of Ge on Si by selective epitaxy and hydrogen annealing 

      Yu, H.-Y.; Park, J.-H.; Okyay, Ali Kemal; Saraswat, K. C. (2008-10)
      We demonstrate a promising approach for the monolithic integration of Ge-based nanoelectronics and nanophotonics with S-ilicon: the selective deposition of Ge on Si by Multiple Hydrogen Annealing for Heteroepitaxy (MHAH). ...

    • Effect of growth pressure on coalescence thickness and crystal quality of GaN deposited on 4H-SiC 

      Caban, P.; Strupinski, W.; Szmidt, J.; Wojcik, M.; Gaca, J.; Kelekci, O.; Caliskan, D.; Özbay, Ekmel (Elsevier, 2010-09-25)
      The influence of growth pressure on the coalescence thickness and the crystal quality of GaN deposited on 4HSiC by low pressure metalorganic vapor phase epitaxy was studied. It was shown that growth pressure has an impact ...

    • Experimental and theoretical investigation of phosphorus in-situ doping of germanium epitaxial layers 

      Yu, H. -Y.; Battal, E.; Okyay, Ali Kemal; Shim, J.; Park J. -H.; Baek, J. W.; Saraswat, K. C. (Elsevier, 2013)
      We investigate phosphorus in-situ doping characteristics in germanium (Ge) during epitaxial growth by spreading resistance profiling analysis. In addition, we present an accurate model for the kinetics of the diffusion in ...

    • High performance n-MOSFETs with novel source/drain on selectively grown Ge on Si for monolithic integration 

      Yu, H.-Y.; Kobayashi, M.; Jung, W. S.; Okyay, Ali Kemal; Nishi, Y.; Saraswat, K. C. (IEEE, 2009)
      We demonstrate high performance Ge n-MOSFETs with novel raised source/drain fabricated on high quality single crystal Ge selectively grown heteroepitaxially on Si using Multiple Hydrogen Anealing for Heteroepitaxy(MHAH) ...

    • High-performance solar-blind AlGaN Schottky photodiodes 

      Bıyıklı, Necmi; Kartaloglu, T.; Aytur, O.; Kimukin, I.; Özbay, Ekmel (Materials Research Society, 2003)
      High-performance solar-blind AlGaN-based Schottky photodiodes have been demonstrated. The detectors were fabricated on MOCVD-grown AlGaN/GaN heterostructures using a microwave-compatible fabrication process. Current-voltage, ...

    • High-Speed InSb photodetectors on GaAs for mid-IR applications 

      Kimukin, I.; Bıyıklı, Necmi; Kartaloǧlu, T.; Aytür, O.; Özbay, Ekmel (IEEE, 2004)
      We report p-i-n type InSb-based high-speed photodetectors grown on GaAs substrate. Electrical and optical properties of photodetectors with active areas ranging from 7.06 × 10 -6 cm 2 to 2.25 × 10 -4 cm 2 measured at 77 K ...

    • High-speed solar-blind AlGaN Schottky photodiodes 

      Bıyıklı, Necmi; Kimukin, İbrahim; Kartaloğlu, Tolga; Aytür, Orhan; Özbay, Ekmel (Cambridge University Press, 2003)
      We report high-speed solar-blind AlGaN-based Schottky photodiodes. AlGaN/GaN heterostructure device layers were grown on sapphire substrate. The devices were fabricated on AlGaN/GaN heterostructuresusing a microwave ...

    • High-speed visible-blind resonant cavity enhanced AlGaN Schottky photodiodes 

      Bıyıklı, Necmi; Kartaloglu, T.; Aytur, O.; Kimukin, I.; Özbay, Ekmel (Materials Research Society, 2003)
      We have designed, fabricated and tested resonant cavity enhanced visible-blind AlGaN-based Schottky photodiodes. The bottom mirror of the resonant cavity was formed with a 20 pair AlN/Al 0.2Ga 0.8N Bragg mirror. The devices ...

    • InGaN/GaN based LEDs with electroluminescence in violet, blue, and green tuned by epitaxial growth temperature 

      Sarı, Emre; Nizamoğlu, Sedat; Özel, Tuncay; Demir, Hilmi Volkan; İnal, Ayşe; Ülker, Erkin; Özbay, Ekmel; Dikme, Y.; Heuken, M. (IEEE, 2007)
      In this work, we present a full set of InGaN LEDs based on a single optimal InGaN/GaN quantum design with emission wavelengths spanning from green to blue to violet by tuning the active layer growth temperature to precisely ...

    • Integrated AlGaN quadruple-band ultraviolet photodetectors 

      Gökkavas, M.; Butun, S.; Caban, P.; Strupinski, W.; Özbay, Ekmel (IOP Publishing, 2012-04-27)
      Monolithically integrated quadruple back-illuminated ultraviolet metalsemiconductormetal photodetectors with four different spectral responsivity bands were demonstrated on each of two different Al xGa 1-xN heterostructures. ...

    • Low-temperature and high-quality growth of Bi2O2Se layered semiconductors via cracking metal–organic chemical vapor deposition 

      Kang, M.; Chai, H. J.; Jeong, H. B.; Park, C.; Jung, In-Y.; Park, E.; Çiçek, Mert Miraç; Lee, I.; Bae, B. S.; Durgun, Engin; Kwak, J. Y.; Song, S.; Choi, S. Y.; Jeong, Hu Y.; Kang, K. (American Chemical Society, 2021-05-25)
      Ternary metal-oxy-chalcogenides are emerging as next-generation layered semiconductors beyond binary metal-chalcogenides (i.e., MoS2). Among ternary metal-oxy-chalcogenides, especially Bi2O2Se has been demonstrated in ...

    • Model study of a surfactant on the GaAs(100) surface 

      Consorte, C. D.; Fong, C. Y.; Watson, M. D.; Yang, L. H.; Çıracı, Salim (Elsevier, 2002-11-01)
      Based on the facts that: (a) the transverse acoustic vibrational branch frequency is softened at the Brillouin zone boundaries of crystalline GaAs; (b) at the surface, the Ga-As bond is stronger than Ga-Te bond; and (c) ...

    • Nanocrystal hybridized white light sources integrated on near UV leds 

      Nizamoğlu, Sedat; Demir, Hilmi Volkan (World Scientific Publishing, 2007)
      We report on CdSe/ZnS core-shell nanocrystal (NC) based white light sources integrated on near-UV InGaN/GaN light emitting diodes (LEDs). We present the design, epitaxial growth, fabrication, integration and characterization ...

    • Near-UV InGaN/GaN-based dual-operation quantum optoelectronic devices 

      Özel, Tuncay; Sarı, Emra; Nizamoğlu, Sedat; Demir, Hilmi Volkan (SPIE, 2007)
      We present a novel dual-operation InGaN/GaN based quantum optoelectronic device (QOD) that operates as a quantum electroabsorption modulator in reverse bias and as a light emitter in forward bias in the spectral range of ...

    • Resonance broadening and tuning of split ring resonators by top-gated epitaxial graphene on SiC substrate 

      Cakmakyapan, S.; Sahin, L.; Pierini, F.; Strupinski, W.; Özbay, Ekmel (AIP Publishing LLC, 2013)
      Split ring resonators (SRRs) are subwavelength structures that are able to localize and enhance the electromagnetic wave. Controlling the plasmonic resonance behavior of metallic nanostructures, such as SRRs, plays an ...

    • Silicon-Germanium multi-quantum well photodetectors in the near infrared 

      Onaran, E.; Onbasli, M. C.; Yesilyurt, A.; Yu, H. Y.; Nayfeh, A. M.; Okyay, Ali Kemal (Optical Society of American (OSA), 2012)
      Single crystal Silicon-Germanium multi-quantum well layers were epitaxially grown on silicon substrates. Very high quality films were achieved with high level of control utilizing recently developed MHAH epitaxial technique. ...

    • A theoretical model for the epitaxial growth of Si(100) surface 

      Dağ, Sefa (Bilkent University, 2000)
      In this thesis, we investigated atomic scale mechanisms of growth on the Si(lOO) surface. First principles quantum molecular dynamics calculations are performed, where self-consistent field electronic structure calculations ...