Comprehensive characterization of vertical GaN-on-GaN Schottky barrier diodes

P. Vigneshwara Raja*, Christophe Raynaud, Camille Sonneville, Atse Julien Eric N'Dohi, Hervé Morel, Luong Viet Phung, Thi Huong Ngo, Philippe De Mierry, Eric Frayssinet, Hassan Maher, Josiane Tasselli, Karine Isoird, Frédéric Morancho, Yvon Cordier, Dominique Planson

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


This paper reports comprehensive characterization of vertical GaN-on-GaN Schottky barrier diodes (SBDs) fabricated on free-standing GaN substrates. The GaN active layer properties are evaluated by atomic force microscopy (AFM), secondary-ion mass spectrometry (SIMS), micro-Raman spectroscopy, cathodoluminescence (CL), and deep-level transient Fourier spectroscopy (DLTFS). The GaN SBDs exhibit near-unity ideality factor (n = 1.1), promising Schottky barrier height (SBH) of ΦB = 0.82 eV, low turn-on voltage ∼0.56 V, leakage current density of JR < 5.5 × 10−6 Acm−2 at −100 V, breakdown voltage VBR < −200 V, and less interface state density (NSS < 5 × 1012 eV−1 cm−2) at the Ni/GaN Schottky contact. The forward and reverse current transport mechanisms of the SBD are identified by fitting analysis of measured J-V. Weak temperature dependence of ΦB and n is detected from I–V-T measurements. Similar traps at EC - 0.18 eV and EC - 0.56 are identified in the various SBDs from DLTFS, signifying that these traps are omnipresent defects in the epilayer.

Original languageEnglish
Article number105575
JournalMicroelectronics Journal
StatePublished - Oct 2022
Externally publishedYes


  • Current transport
  • Defects
  • Free-standing GaN
  • Material characterization
  • Schottky barrier diode


Dive into the research topics of 'Comprehensive characterization of vertical GaN-on-GaN Schottky barrier diodes'. Together they form a unique fingerprint.

Cite this