Title :
Heterojunction Band Offset Limitations on Open-Circuit Voltage in p-ZnT e/n-ZnSe Solar Cells
Author :
Teran, A.S. ; Chen, C. ; Lopez, E. ; Linares, P.G. ; Artacho, I. ; Marti, A. ; Luque, A. ; Phillips, J.D.
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Univ. of Michigan, Ann Arbor, MI, USA
Abstract :
Limitations on the open-circuit voltage of p-ZnTe/n-ZnSe heterojunction solar cells are studied via current-voltage (I-V) measurements under solar concentration and at variable temperature. The open-circuit voltage reaches a maximum value of 1.95 V at 77 K and 199 suns. The open-circuit voltage shows good agreement with the calculated built-in potential of 2.00 V at 77 K. These results suggest that the open-circuit voltage is limited by heterojunction band offsets associated with the type-II heterojunction band lineup, rather than the bandgap energy of the ZnTe absorber material.
Keywords :
II-VI semiconductors; electrical conductivity; semiconductor heterojunctions; solar cells; wide band gap semiconductors; zinc compounds; I-V measurements; ZnTe-ZnSe; current-voltage measurements; heterojunction band offset limitations; open-circuit voltage; p-ZnTe-n-ZnSe heterojunction solar cells; solar concentration; temperature 77 K; type-II heterojunction band lineup; Electric potential; Heterojunctions; Materials; Photonic band gap; Photovoltaic cells; Photovoltaic systems; Temperature measurement; Heterojunction solar cell; open-circuit voltage; zinc selenide (ZnSe); zinc telluride (ZnTe);
Journal_Title :
Photovoltaics, IEEE Journal of
DOI :
10.1109/JPHOTOV.2015.2411057
