Effects of Phonon Coupling and Free Carriers on Band-Edge Emission at Room Temperature in n-type ZnO Crystals

Abstract

Room-temperature photoluminescence has been studied in II-type bulk ZnO crystals representing three different growth methods and having free-carrier concentrations (n) ranging from 10(exp 13) to 10(exp 18) /cu cm. The near-band-edge emission has both free-exciton and free-exciton-phonon contributions, with the strength of the phonon coupling dependent on sample defect concentrations. Band-gap shrinkage effects are used to explain a decrease in emission energy for the higher n values. Band filling and hand nonparabolicity are predicted to be important for n > 10(exp 19) /cu cm. At 300 K, in the absence of free carriers. the free-exciton energy is 3.312 plus or minus 0.004 eV.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 2006
Accession Number
ADA486852

Entities

People

  • Buguo Wang
  • Chunchuan Xu
  • J. S. Neal
  • L. A. Boatner
  • M. J. Callahan
  • N. C. Giles

Organizations

  • Air Force Research Laboratory

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force
  • Air Force Research Laboratories
  • Band Gaps
  • Couplings
  • Crystal Lattice Vibrations
  • Electrons
  • Emission
  • Energy Bands
  • Energy Gaps
  • Films
  • Materials
  • Materials Science
  • Photoluminescence
  • Physics
  • Radiation
  • Scattering
  • Thin Films

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.

Technology Areas

  • Microelectronics