Analysis of multijunction solar cell degradation in space and irradiation induced recombination centers

Abstract

We demonstrate how, using electroluminescence, the parameters characterizing the recombination center induced by irradiation in a solar cell can be measured. Because electroluminescence is able to provide information on an individual cell in a multijunction (MJ) cell device, independently of the others, we apply this technique to measure these parameters in InGaP/GaAs/Ge MJ cells. We then calculate the variations of the open-circuit voltage and short-circuit current of such cells versus fluence. The results are compared with experimental data obtained for 1 MeV electron irradiations.

Modelling of solar cell degradation in space

“…Studies necessary to get all the necessary data (in unirradiated as well as irradiated materials) for GaAs and GaInP materials have been systematically performed over years: from 1985 to 2005 for GaAs [1][2][3][4][6][7][8]12,19,20,[22][23][24] and from 1998 to 2003 for GaInP [2,5,7,8,[18][19][20]23]. The DLTS technique provides only an order of magnitude for s (through extrapolation to infinite temperature T of the plot log e n versus 1/T determined in a narrow temperature range).…”

“…For instance, an equivalent fluence of 10 16 cm À 2 1 MeV electrons, which corresponds to a typical space condition, introduces a total of 10 16 cm À 3 defects in GaAs (1) while the emitter and base of a cell are doped at a level of several 10 17 cm À 3 . Systematic studies, combining measurements of I-V characteristics in dark and under illumination, electroluminescence, time resolved photoluminescence (TRPL) and deep level transient spectroscopy (DLTS) performed on single GaAs and GaInP junctions, have allowed us to identify, characterize and measure the concentrations and the introduction rates (for 1 MeV electrons only) of the native and irradiation induced defects acting as non-radiative recombination centers in these two materials [1][2][3][4][5][6][7][8].…”

Analytical model for multi-junction solar cells prediction in space environment

“…According to the method developed by Zazoui et al [7], we can determine the evolution of the ''kr'' versus the NIEL. Figs.…”

“…The third method was developed by Bourgoin et al [2]. The aim of this method is the determination of the introduction rates of the dominant recombination center and associated cross section for a given particle energy.…”

Investigation of proton damage in III-V semiconductors by optical spectroscopy

“…However, the space is a hazardous environment containing energetic particles, which lead to degradation of the solar cell efficiency and hence, a decrease in the lifetime of satellites. Many radiation experiments have been performed towards the understanding of the changes of electrical parameters related to the degradation of solar cells [1][2][3][4][5][6]. A complementary approach to experiment is to simulate the damage on different materials produced by heavy and light ions.…”