Si-Ge-Sn alloys with 1.0 eV gap for CPV multijunction solar cells

Journal Article · Mon Sep 28 04:00:00 EDT 2015 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.4931519· OSTI ID:22489010

Roucka, Radek; Clark, Andrew ^[1]; Landini, Barbara ^[2]

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1. Translucent Inc., Palo Alto, CA, 94303 (United States)
2. Sumika Electronic Materials Inc., Phoenix, AZ, 85034 (United States)

Si-Ge-Sn ternary group IV alloys offer an alternative to currently used 1.0 eV gap materials utilized in multijunction solar cells. The advantage of Si-Ge-Sn is the ability to vary both the bandgap and lattice parameter independently. We present current development in fabrication of Si-Ge-Sn alloys with gaps in the 1.0 eV range. Produced material exhibits excellent structural properties, which allow for integration with existing III-V photovoltaic cell concepts. Time dependent room temperature photoluminescence data demonstrate that these materials have long carrier lifetimes. Absorption tunable by compositional changes is observed. As a prototype device set utilizing the 1 eV Si-Ge-Sn junction, single junction Si-Ge-Sn device and triple junction device with Si-Ge-Sn subcell have been fabricated. The resulting I-V and external quantum efficiency data show that the Si-Ge-Sn junction is fully functional and the performance is comparable to other 1.0 eV gap materials currently used.

• OSTI ID: 22489010
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1679; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
CARRIER LIFETIME
COMPARATIVE EVALUATIONS
EV RANGE
FABRICATION
GERMANIUM ALLOYS
LATTICE PARAMETERS
PERFORMANCE
PHOTOLUMINESCENCE
QUANTUM EFFICIENCY
SEMICONDUCTOR JUNCTIONS
SILICON ALLOYS
SOLAR CELLS
TEMPERATURE RANGE 0273-0400 K
TERNARY ALLOY SYSTEMS
TIME DEPENDENCE
TIN ALLOYS