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Inside Back Cover: Effects of polarization charge on the photovoltaic properties of InGaN solar cells (Phys. Status Solidi A 4/2011)
Author(s) -
Li Z. Q.,
Lestradet M.,
Xiao Y. G.,
Li S.
Publication year - 2011
Publication title -
physica status solidi (a)
Language(s) - English
Resource type - Reports
SCImago Journal Rank - 0.532
H-Index - 104
eISSN - 1862-6319
pISSN - 1862-6300
DOI - 10.1002/pssa.201190012
Subject(s) - optoelectronics , materials science , polarization (electrochemistry) , electric field , photovoltaic system , charge carrier , solar cell , open circuit voltage , band gap , wide bandgap semiconductor , piezoelectricity , voltage , chemistry , physics , electrical engineering , quantum mechanics , composite material , engineering
The effects of interface polarization charge on the photovoltaic characteristics of GaN/InGaN solar cells have been analyzed by Z.Q. Li et al. (pp. 928–931) using 2D drift–diffusion simulations. InGaN material could be potentially used for high efficient solar cells thanks to its wide band‐gap range, high absorption coefficient and radiation hardness. However, it is well‐known that spontaneous polarization and strain‐induced piezoelectric polarization effect lead to significant interface charges in nitride‐based devices grown on c‐plane. For common Ga‐polar (0001) InGaN solar cells, the polarization charge at the GaN/InGaN interface creates an electric field that forces photo carriers to drift in opposite directions needed for efficient collection and substantially reduces the short circuit current ( I sc ) and open circuit voltage ( V oc ). Using N‐polar (000 $\bar{1}$ ) InGaN materials, on the other hand, the polarization charges reverse signs and the subsequent electric field helps to sweep the photo carriers to proper contacts.