Defect Studies on Fast and Thermal Neutron Irradiated GaN

2008

Single crystalline epitaxial GaN films were irradiated with fast (E > 1 MeV) or with fast and thermal neutrons. These irradiation conditions allow the separation of the effect of transmutational doping with Ge due to nuclear reactions with thermal neutrons on the damage production. High resolution X-ray diffraction showed an expansion of the c-lattice parameter after irradiation which is reversed after annealing at 1000 C. The effect of neutron irradiation on the optical properties of GaN samples was investigated using photoluminescence and Raman spectroscopies. With above band gap excitation the PL spectra of the as-irradiated sample with fast and thermal neutrons is dominated by broad emission bands in the UV and yellow spectral range whereas no PL is observed for the fast neutron as irradiated sample. Annealing the as-irradiated samples promotes the damage recovery and noticed changes are observed in the PL spectra. Raman scattering spectra indicate an increase of the intensity of the disorder activated phonons revealing higher lattice damage for the irradiation with fast and thermal neutrons.

Autores da comunidade :

• 

  K

  Katharina Lorenz

  ist25461

  Afiliações e fontes

  De: orcid

  ID: 55722859

• 

  J

  José Joaquim Gonçalves Marques

  ist25367

  Afiliações e fontes

  IST > DECN

  Departamento de Engenharia e Ciências Nucleares

  De: orcid

  ID: 10677343

• 

  N

  Nuno Pedro Serras Lucas Nobre Franco

  ist25566

• 

  E

  Eduardo Jorge Da Costa Alves

  ist25357

  Afiliações e fontes

  De: orcid

  ID: 10761569

• 

  M

  Marco António Baptista Peres

  ist28008

  Afiliações e fontes

  De: orcid

  ID: 13945327

NA - Versão desconhecida

Elsevier

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

2780

2783

266

12-13

0168-583X

10.1016/j.nimb.2008.03.116

physical-sciences - Física

eng - Inglês