Stress relaxation in Si-doped GaN studied by Raman spectroscopy

In Hwan Lee, In Hoon Choi, Cheul Ro Lee, Eun Joo Shin, Dongho Kim, Sam Kyu Noh, Sung Jin Son, Ki Yong Lim, Hyung Jae Lee

Research output: Contribution to journalArticle

70 Citations (Scopus)

Abstract

We report the Si-doping-induced relaxation of residual stress in GaN epitaxial layers grown on (0001) sapphire substrate by the metalorganic vapor phase epitaxy technique. Micro-Raman spectroscopy is used to assess stress situation in the films with systematically modulated doping concentration from 4.0×1017 up to 1.6×1019 cm-3. As the Si-doping concentration increases, a monotonie decrease of the E2 phonon frequency is observed, which signifies gradual relaxation of the stress in the film. The layers are fully relaxed when electron concentration exceeds 1.6 ×1019 cm-3. The linear coefficient of shift in Raman frequency (ω) induced by the in-plane biaxial compressive stress (σ) is estimated to be Δω/Δσ=7.7 cm-1/GPa. We suggest that Si doping increases density of misfit dislocation, judging from linewidth of x-ray rocking curve.

Original languageEnglish
Pages (from-to)5787-5791
Number of pages5
JournalJournal of Applied Physics
Volume83
Issue number11
DOIs
Publication statusPublished - 1998 Jun 1

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Stress relaxation in Si-doped GaN studied by Raman spectroscopy'. Together they form a unique fingerprint.

  • Cite this

    Lee, I. H., Choi, I. H., Lee, C. R., Shin, E. J., Kim, D., Noh, S. K., Son, S. J., Lim, K. Y., & Lee, H. J. (1998). Stress relaxation in Si-doped GaN studied by Raman spectroscopy. Journal of Applied Physics, 83(11), 5787-5791. https://doi.org/10.1063/1.367501