Lattice-matched GaNPAs-on-silicon tandem solar cells

Author

Geisz, J.F. ; Olson, J.M. ; Friedman, D.J. ; Jones, K.M. ; Reedy, R.C. ; Romero, M.J.

Author_Institution

Nat. Renewable Energy Lab., Golden, CO, USA

fYear

2005

fDate

3-7 Jan. 2005

Firstpage

695

Lastpage

698

Abstract

A two-junction device consisting of a 1.7-eV GaNPAs junction on a 1.1 -eV silicon junction has the theoretical potential to achieve nearly optimal efficiency for a two-junction tandem cell. We have demonstrated a monolithic III-V-on-silicon tandem solar cell in which most of the III-V layers are nearly lattice-matched to the silicon substrate. The cell includes a 1.8 eV GaNPAs top cell, a GaP-based tunnel junction (TJ), and a diffused silicon junction formed during the epitaxial growth of GaNP on the silicon substrate. This tandem on silicon has a V_OC of 1.53 V and an AM1.5G efficiency of 5.2% without any antireflection coating. Low currents in the top cell are the primary limitation to higher efficiency at this point.

Keywords

III-V semiconductors; elemental semiconductors; gallium arsenide; gallium compounds; semiconductor epitaxial layers; semiconductor junctions; silicon; solar cells; 1.1 -eV silicon junction; 1.53 V; 1.7-eV GaNPAs junction; 1.8 eV GaNPAs top cell; 5.2 percent; GaNPAs-GaP-Si; GaNPAs-on-silicon tandem solar cells; GaP-based tunnel junction; III-V layers; Si; antireflection coating; diffused silicon junction; epitaxial growth; lattice matching; monolithic III-V-on-silicon tandem solar cell; optimal efficiency; two-junction device; Abstracts; Buffer layers; Epitaxial growth; Gallium arsenide; Laboratories; Photonic band gap; Photovoltaic cells; Renewable energy resources; Silicon; Substrates;

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.2005.1488226

Filename

1488226