SiGe thin-film structures for solar cells

Conference · Thu Dec 31 04:00:00 EST 1998

OSTI ID:323638

Bremond, G; Daami, A; Laugier, A ^[1]

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1. Inst. National des Sciences Appliquees de Lyon, Villeurbanne (France). Lab. de Physique de la Matiere; and others

In order to study their applicability as the active base material in Si thin crystalline film solar cell technology, SiGe relaxed layers grown by Liquid Phase Epitaxy (LPE) and Chemical Vapor Deposition (CVD) on Si substrates are investigated by optical and electrical measurements (TEM, EXD, PL, EBIC). The main results of this work is to point out the improvement of the SiGe active base layer by using smooth Ge graded SiGe buffer layer and remote plasma hydrogenation. TEM, EXD, PL experiments show the effect of the Ge graded buffer layer grown using LPE, by confining the threading dislocations in the SiGe buffer layer close to the Si/SiGe interface. EBIC measurements reveal low recombination activity of dislocations at 300 K providing the diffusion length exceeds the 15 {micro}m layer thickness. The enhanced luminescence of SiGe near bandgap indicates that remote plasma hydrogenation induces a decrease of the non-radiative recombination pathways due to dislocations on CVD layers where defect recombinations dominate as indicated by EBIC measurements. This study points out the importance of controlling relaxed SiGe layers with good minority carrier recombination quality as a key issue for the optimization of new SiGe/Si based solar cells.

• OSTI ID: 323638
• Report Number(s): CONF-971201--
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
CHARGE CARRIERS
CHEMICAL VAPOR DEPOSITION
DIFFUSION LENGTH
DISLOCATIONS
GERMANIUM SILICIDES
LIQUID PHASE EPITAXY
LUMINESCENCE
RECOMBINATION
SILICON SOLAR CELLS