Determination of band tail widths in MOCVD grown InGaN single layer within GaN based p-i-n LED structure through photo-induced measurements

Özdemir O., Bozkurt K., Ayarcı Kuruoğlu N., Baş H., Sarcan F., Erol A., ...More

JOURNAL OF LUMINESCENCE, vol.255, pp.119543, 2023 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 255
  • Publication Date: 2023
  • Doi Number: 10.1016/j.jlumin.2022.119543
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Chemical Abstracts Core, Communication Abstracts, INSPEC
  • Page Numbers: pp.119543
  • Keywords: Surface photo -voltage, Spectral photo -conductivity, InGaN layer, Franz-Keldysh effect
  • Yıldız Technical University Affiliated: Yes


Within a p-i-n LED structure, energy band gaps of MOCVD grown %10 In content InGaN and GaN layers were obtained through traditional UV–Visible transmission-absorption measurements and utilizing surface photovoltage (SPV) and spectral photoconductivity (SPC) measurements. Moreover, all applied techniques determined that the total band offset between InGaN and GaN layers were around 0.3–0.4 eV. Furthermore, the temperature dependence of band gaps of each InGaN and GaN layer was analyzed through a modified Varshni relation where both Varshni coefficients and band tail energy width were explored. Band tails in a modified Varshni relation, SPV and SPC measurements were in agreement with each other and originated Franz-Keldysh Effect attributed to the presence of photon assisted tunneling.