Now showing items 1-10 of 10

    • Analysis of defect related optical transitions in biased AlGaN/GaN heterostructures 

      Bengi, A.; Lisesivdin, S.B.; Kasap, M.; Mammadov, T.; Ozcelik, S.; Ozbay, E. (2010)
      The optical transitions in AlGaN/GaN heterostructures that are grown by metalorganic chemical vapor deposition (MOCVD) have been investigated in detail by using Hall and room temperature (RT) photoluminescence (PL) ...
    • Analyzing the AlGaN/AlN/GaN heterostructures for HEMT applications 

      K. Durukan, İ.; Akpınar, Ö.; Avar, C.; Gultekin, A.; Öztürk, M. K.; Özçelik, S.; Özbay, E. (American Scientific Publishers, 2018-03)
      In the present work, we have reported two high-electron-mobility transistor structures (HEMTs) with different thick AlN buffer deposited on sapphire substrates by metal-organic chemical vapor deposition (MOCVD). AlN buffer ...
    • Contributions of impurity band and electron-electron interactions to magnetoconductance in AlGaN 

      Tasli, P.; Yildiz, A.; Kasap, M.; Ozbay, E.; Lisesivdin, S. B.; Ozcelik, S. (Taylor & Francis, 2010-06-30)
      Low temperature electrical measurements of conductivity, the Hall effect and magnetoconductance were performed on a degenerate AlGaN sample. The sample exhibited negative magnetoconductance at low magnetic fields and low ...
    • Effect of reactor pressure on optical and electrical properties of InN films grown by high-pressure chemical vapor deposition 

      Alevli, M.; Gungor, N.; Alkis, S.; Ozgit Akgun, C.; Donmez, I.; Okyay, A., K.; Gamage, S.; Senevirathna, I.; Dietz, N.; Biyikli, N. (Wiley - V C H Verlag GmbH & Co. KGaA, 2015)
      The influences of reactor pressure on the stoichiometry, free carrier concentration, IR and Hall determined mobility, effective optical band edge, and optical phonon modes of HPCVD grown InN films have been analysed and ...
    • The effect of strain relaxation on electron transport in undoped Al0.25Ga0.75N/GaN heterostructures 

      Lişesivdin, S. B.; Yıldız, A.; Acar, S.; Kasap, M.; Özçelik, S.; Özbay, E. (Elsevier BV * North-Holland, 2007-11-01)
      The two-dimensional electron gas (2DEG) transport properties of two-step growth undoped Al0.25Ga0.75N/GaN heterostructures with semi-insulating buffer, grown by MOCVD, were investigated in a temperature range of 20–350 ...
    • Examination of the temperature related structural defects of InGaN/GaN solar cells 

      Durukan, İ. K.; Bayal, Ö.; Kurtuluş, G.; Baş, Y.; Gültekin, A.; Öztürk, M. K.; Çörekçi, S.; Tamer, M.; Özçelik, S.; Özbay, E. (Academic Press, 2015)
      In this study the effects of the annealing temperature on the InGaN/GaN solar cells with different In-contents grown on sapphire substrate by the Metal Organic Chemical Vapor Deposition (MOCVD) are analyzed by High Resolution ...
    • Forward tunneling current in Pt/p-InGaN and Pt/n-InGaN Schottky barriers in a wide temperature range 

      Arslan, E.; Çakmak, H.; Özbay, E. (Elsevier, 2012-07-27)
      The current-transport mechanisms of the Pt contacts on p-InGaN and n-InGaN were investigated in a wide temperature range (80-360 K) and in the forward bias regime. It was found that the ideality factor (n) values and ...
    • InGaN green light emitting diodes with deposited nanoparticles 

      Butun, B.; Cesario J.; Enoch, S.; Quidant, R.; Ozbay, E. (Elsevier BV, 2007)
      We grew an InGaN/GaN-based light-emitting diode (LED) wafer by metal-organic chemical vapor deposition (MOCVD), fabricated devices by optical lithography, and successfully deposited ellipsoidal Ag nano-particles by way of ...
    • Microstructural analysis with graded and non-graded indium in InGaN solar cell 

      Durukan, I. K.; Öztürk, M. K.; Çörekçi, S.; Tamer, M.; Baş, Y.; Özçelik, S.; Özbay, Ekmel (American Scientific Publishers, 2017)
      In this study are graded and non graded InGaN/GaN samples grown on c-oriented sapphire substrate using the Metal Organic Chemical Vapour Deposition (MOCVD) technique. The structural and morphological properties of the grown ...
    • Ultraviolet-visible nanophotonic devices 

      Bütün, Bayram (Bilkent University, 2010)
      Recently in semiconductor market, III-Nitride materials and devices are of much interest due to their mechanical strength, radiation resistance, working in the spectrum from visible down to the deep ultraviolet region ...