TY - GEN
T1 - Effect of Ge/Si heterostructures on carrier extraction in Si solar cells with Ge quantum dots
AU - Tayagaki, Takeshi
AU - Hoshi, Yusuke
AU - Ooi, Kazufumi
AU - Kiguchi, Takanori
AU - Usami, Noritaka
PY - 2013/1/1
Y1 - 2013/1/1
N2 - Solar cells using quantum dots (QDs) have been extensively studied, in many of which the open circuit voltage (Voc) always decreases. The mechanism of this Voc reduction has not been understood well. We studied Si solar cells with multi-stacked Ge QDs (Ge/Si QD solar cells), in which the type-II Ge/Si band offsets are formed. From the current-voltage characteristics, the Voc is found to increase at low temperatures, indicating that the Voc reduction is due to thermal excitation of carriers. By comparing solar cells with different Ge thicknesses, we found that the Voc reduction depends strongly on the Ge thickness.
AB - Solar cells using quantum dots (QDs) have been extensively studied, in many of which the open circuit voltage (Voc) always decreases. The mechanism of this Voc reduction has not been understood well. We studied Si solar cells with multi-stacked Ge QDs (Ge/Si QD solar cells), in which the type-II Ge/Si band offsets are formed. From the current-voltage characteristics, the Voc is found to increase at low temperatures, indicating that the Voc reduction is due to thermal excitation of carriers. By comparing solar cells with different Ge thicknesses, we found that the Voc reduction depends strongly on the Ge thickness.
KW - Germanium
KW - Photovoltaic cells
KW - Quantum dots
KW - Semiconductor nanostructures
KW - Silicon
UR - http://www.scopus.com/inward/record.url?scp=84896473402&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84896473402&partnerID=8YFLogxK
U2 - 10.1109/PVSC.2013.6744160
DO - 10.1109/PVSC.2013.6744160
M3 - Conference contribution
AN - SCOPUS:84896473402
SN - 9781479932993
T3 - Conference Record of the IEEE Photovoltaic Specialists Conference
SP - 330
EP - 332
BT - 39th IEEE Photovoltaic Specialists Conference, PVSC 2013
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 39th IEEE Photovoltaic Specialists Conference, PVSC 2013
Y2 - 16 June 2013 through 21 June 2013
ER -