Evolution of defect complexes in InGaAsN

Author

Khan, Aurangzeb ; Kurtz, Sarah R. ; Prasad, S. ; Johnston, S.W.

Author_Institution

Dept. of Electr. & Comput. Eng., Univ. of South Alabama, Mobile, AL, USA

fYear

2005

Firstpage

731

Lastpage

734

Abstract

The thermal annealing of nitrogen related traps in p-type InGaAsN and GaAsN is investigated by deep level transient spectroscopy (DLTS). Upon annealing, an apparent recovery of the photovoltaic properties correlates with changes in the DLTS data observed for InGaAsN and GaAsN diodes and solar cells, revealing that a nitrogen related E1 (E_C-0.20 eV) center has an important role in governing the solar cell performance. The large electron capture cross section (∼8.9 × 10^-15 cm²) of this center indicates that this defect may act as an efficient recombination center. Therefore, its complete removal by annealing or by some other process is essential for the high performance of GaInAsN solar cells. The internal quantum efficiency (IQE) data were modeled to quantify the change in material properties associated with this improvement upon annealing. Annealed cells with indium impurity (InGaAsN) show a slightly higher photoresponse, which could be due to low scattering caused by In-N pair formation after annealing.

Keywords

III-V semiconductors; annealing; deep level transient spectroscopy; electron traps; gallium arsenide; gallium compounds; hole traps; impurities; indium compounds; point defects; semiconductor diodes; solar cells; DLTS; GaAsN; GaAsN diodes; GaAsN solar cells; In-N pair formation; InGaAsN; InGaAsN diodes; InGaAsN solar cells; deep level transient spectroscopy; defect complex evolution; electron capture cross section; indium impurity; internal quantum efficiency; nitrogen related E1 center; nitrogen related traps; p-type GaAsN; p-type InGaAsN; photoresponse; photovoltaic properties; recombination center; scattering; thermal annealing; Annealing; Diodes; Nitrogen; Photovoltaic cells; Photovoltaic systems; Radiative recombination; Radioactive decay; Solar power generation; Spectroscopy; Spontaneous emission;

fLanguage

English

Publisher

ieee

Conference_Titel

Photovoltaic Specialists Conference, 2005. Conference Record of the Thirty-first IEEE

ISSN

0160-8371

Print_ISBN

0-7803-8707-4

Type

conf

DOI

10.1109/PVSC.2005.1488236

Filename

1488236