G. S. Khrypunov
Kharkiv Polytechnical Institute, National Technical University, Kharkiv, Ukraine
V. R. Kopach
Kharkiv Polytechnical Institute, National Technical University, Kharkiv, Ukraine
M. V. Kirichenko
Kharkiv Polytechnical Institute, National Technical University, Kharkiv, Ukraine
R. V. Zaitsev
Kharkiv Polytechnical Institute, National Technical University, Kharkiv, Ukraine
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http://dx.doi.org/10.3384/ecp110572780Published in: World Renewable Energy Congress - Sweden; 8-13 May; 2011; Linköping; Sweden
Linköping Electronic Conference Proceedings 57:12, p. 2780-2786
Published: 2011-11-03
ISBN: 978-91-7393-070-3
ISSN: 1650-3686 (print), 1650-3740 (online)
The aim of research was development of the improved designs of high-efficiency single-crystal Si solar cells (Si-SC); intended for work in the conditions of ordinary and high-concentrated sun radiation; and also finding out of possibility to use of such devices as energy independent and enough sensitive sensors in the optical location systems. It was shown that for increase of the efficiency at cost reduction and production manufacturability of single-crystal Si-SC with base crystals (BC) thickness 180 = tBC = 200 µm having a polished light receiving surface (LRS) and back surface reflector (BSR) consisting of a transparent oxide and Al layers; a conductive transparent indium-tin oxide (ITO) layer oft?O = 0.25 µm interference thickness without of perforation is to be used. In case of Si-SC with inverted pyramid type texture of LRS at which the specificity of light distribution in the BC causes essentially total internal reflection of radiation from Si/ITO interface; the t?O value should be optimized in the 1÷2 µm range independently of tBC. For efficiency increase of vertical multijunction (VMJ) Si-SC by a factor of 1.2 approximately the modernization of in series connected unit diode structures (UDS) by the introduction along their vertical Si-boundaries single-layer ITO reflectors by thickness more than 1 µm is promising too. Accordingly to results of numerical simulation the character of open circuit voltage U dependence on a angle value of light incidence onto LRS of VMJ Si-SC considerable depends on the minority charge carriers lifetime t value in the BC of VMJ Si-SC; while light reflection coefficient R value for UDS Si/ITO boundaries effects on absolute UOC value. It has been shown that purposeful decrease of t value and providing of 95 < R < 100 % should allowed to create the VMJ Si-SC with practically linear and easily registered UOC(a) dependence for use the VMJ Si-SC as energy independent and enough sensitive sensors in the optical location systems.
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