Low-frequency noise in GaN thin films deposited by rf-plasma assisted molecular-beam epitaxy

B. H. Leung, W. K. Fong, C. F. Zhu, Charles Surya

Research output: Contribution to journalArticlepeer-review

10 Citations (Scopus)


We report detailed investigations of low-frequency excess noise in GaN thin-film cross-bridge structures deposited by rf-plasma assisted molecular-beam epitaxy on top of an intermediate-temperature buffer layer (ITBL) grown at 690°C. The experimental data indicates strong dependence of the voltage noise power spectra on the thickness of the ITBL with an optimal thickness of 800 nm. A model has been presented to account for the observed noise, which stipulates that the phenomenon arises from the thermally activated trapping and detrapping of carriers. The process results in the correlated fluctuations in both the carrier number and the Coulombic scattering rate. Detailed computation shows that number fluctuation dominates in our samples. Our numerical evaluation indicates a reduction in the trap density by over an order of magnitude with the use of an ITBL in the growth of GaN thin films.

Original languageEnglish
Pages (from-to)3706-3710
Number of pages5
JournalJournal of Applied Physics
Issue number6
Publication statusPublished - Mar 15 2002
Externally publishedYes

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Low-frequency noise in GaN thin films deposited by rf-plasma assisted molecular-beam epitaxy'. Together they form a unique fingerprint.

Cite this