Tampere University of Technology

TUTCRIS Research Portal

Photovoltaic properties of low-bandgap (0.7–0.9 eV) lattice-matched GaInNAsSb solar junctions grown by molecular beam epitaxy on GaAs

Research output: Contribution to journalArticleScientificpeer-review

Details

Original languageEnglish
Pages (from-to)198-203
Number of pages6
JournalSolar Energy Materials and Solar Cells
Volume195
DOIs
Publication statusPublished - 15 Jun 2019
Publication typeA1 Journal article-refereed

Abstract

We demonstrate single junction GaInNAsSb solar cells with high nitrogen content, i.e. in the range of 5–8%, and bandgap energies close to 0.7 eV grown by molecular beam epitaxy. A good crystalline quality is demonstrated for the entire range of N concentrations. An average external quantum efficiency of 0.45 is demonstrated for GaInNAsSb solar cell with 6.2% N exhibiting a bandgap of 0.78 eV (no antireflection coatings has been applied). The internal quantum efficiency for the cell is 0.65 at E g + 0.2 eV. The solar cells exhibited bandgap-voltage offsets between 0.55 V (for N = 5.3%) and 0.66 V (for N = 7.9%). When used in a six-junction solar cell architecture under AM1.5D illumination, the estimated short-circuit current density corresponding to the 0.78 eV cell is 8.2 mA/cm 2 . Furthermore, using the parameters obtained for the GaInNAsSb junction with 6.2% N, we have estimated that such six-junction solar cell architecture could realistically attain an efficiency of over 50% at 1000 suns concentration.

Keywords

  • Dilute nitrides, GaInNAsSb, Molecular beam epitaxy, Multijunction solar cells

Publication forum classification

Field of science, Statistics Finland