TY - JOUR
T1 - Light-Induced Effects on the a-Si
T2 - H/c-Si Heterointerface
AU - Vasudevan, Ravi
AU - Poli, Isabella
AU - Deligiannis, Dimitrios
AU - Zeman, Miro
AU - Smets, Arno H.M.
PY - 2016/12/16
Y1 - 2016/12/16
N2 - Light-induced effects on the minority carrier lifetime of silicon heterojunction structures are studied through multiple-exposure photoconductance decay (MEPCD). MEPCD monitors the effect of the measurement flash from a photoconductance decay setup on a sample over thousands of measurements. Varying the microstructure of the intrinsic hydrogenated amorphous silicon (a-Si:H) used for passivation of n-Type crystalline silicon (c-Si) showed that passivating films rich in voids produce light-induced improvement, while denser films result in samples that are susceptible to light-induced degradation. Light-induced degradation is linked to an increase in dangling bond density at the a-Si:H/c-Si interface, while light-induced improvements are linked to charging at the a-Si:H/c-Si interface. Furthermore, doped a-Si:H is added to make samples with an emitter and back surface field (BSF). These doped layers have a significant effect on the light-induced kinetics on minority carrier lifetime. Emitter samples exhibit consistent light-induced improvement, while BSF samples exhibit light-induced degradation. This is explained through negative charging at the BSF and positive charging at the emitter. Full precursors with a BSF and emitter exhibit different kinetics based on which side is being illuminated. This suggests that the light-induced charging at the a-Si:H/c-Si interface can only occur when a-Si:H has sufficient generation.
AB - Light-induced effects on the minority carrier lifetime of silicon heterojunction structures are studied through multiple-exposure photoconductance decay (MEPCD). MEPCD monitors the effect of the measurement flash from a photoconductance decay setup on a sample over thousands of measurements. Varying the microstructure of the intrinsic hydrogenated amorphous silicon (a-Si:H) used for passivation of n-Type crystalline silicon (c-Si) showed that passivating films rich in voids produce light-induced improvement, while denser films result in samples that are susceptible to light-induced degradation. Light-induced degradation is linked to an increase in dangling bond density at the a-Si:H/c-Si interface, while light-induced improvements are linked to charging at the a-Si:H/c-Si interface. Furthermore, doped a-Si:H is added to make samples with an emitter and back surface field (BSF). These doped layers have a significant effect on the light-induced kinetics on minority carrier lifetime. Emitter samples exhibit consistent light-induced improvement, while BSF samples exhibit light-induced degradation. This is explained through negative charging at the BSF and positive charging at the emitter. Full precursors with a BSF and emitter exhibit different kinetics based on which side is being illuminated. This suggests that the light-induced charging at the a-Si:H/c-Si interface can only occur when a-Si:H has sufficient generation.
KW - Hydrogenated amorphous silicon (a-Si:H)
KW - light-induced degradation (LID)
KW - silicon heterojunction (SHJ)
UR - http://www.scopus.com/inward/record.url?scp=85007390508&partnerID=8YFLogxK
UR - http://resolver.tudelft.nl/uuid:9dc89b86-b554-4593-8f17-cd83db6b8633
U2 - 10.1109/JPHOTOV.2016.2633800
DO - 10.1109/JPHOTOV.2016.2633800
M3 - Article
AN - SCOPUS:85007390508
SN - 2156-3381
VL - 7
SP - 656
EP - 664
JO - IEEE Journal of Photovoltaics
JF - IEEE Journal of Photovoltaics
IS - 2
M1 - 7786911
ER -