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

ÖZDEMİR O., BOZKURT K., AYARCI KURUOĞLU N., Baş H., SARCAN F., EROL A., ...More

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

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

Abstract

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 photo -voltage (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.