Optical properties of GaN pyramids

K. C. Zeng, J. Y. Lin, H. X. Jiang, Wei Yang

Research output: Contribution to journalArticlepeer-review

62 Scopus citations


Picosecond time-resolved photoluminescence (PL) spectroscopy has been used to investigate the optical properties of GaN pyramids overgrown on hexagonal-patterned GaN(0001) epilayers on sapphire and silicon substrates with AlN buffer layers. We found that: (i) the release of the biaxial compressive strain in GaN pyramids on GaN/AlN/sapphire substrate led to a 7 meV redshift of the spectral peak position with respect to the strained GaN epilayer grown under identical conditions; (ii) in the GaN pyramids on GaN/AlN/sapphire substrate, strong band edge transitions with much narrower linewidths than those in the GaN epilayer have been observed, indicating the improved crystalline quality of the overgrown pyramids; (iii) PL spectra taken from different parts of the pyramids revealed that the top of the pyramid had the highest crystalline quality; and (iv) the presence of strong band-to-impurity transitions in the pyramids were primarily due to the incorporation of the oxygen and silicon impurities from the SiO2 mask.

Original languageEnglish
Pages (from-to)1227-1229
Number of pages3
JournalApplied Physics Letters
Issue number9
StatePublished - Mar 1 1999


Dive into the research topics of 'Optical properties of GaN pyramids'. Together they form a unique fingerprint.

Cite this