Study on the damage effects of 940nm pulsed laser on tri-junction GaAs solar cells

In the study of multi-pulse laser damage to solar cells, triple-junction GaAs solar cells were irradiated with a pulsed laser of 1.58ms pulse width and 940 nm wavelength to investigate the effects of laser ablation on the surface morphology and performance of the cells. By adjusting the laser irradiation time (one second, three seconds, and five seconds) and varying the laser power density, the surface damage characteristics and changes in current-voltage properties after multi-pulse laser irradiation were systematically analyzed. The experimental results showed that as the laser irradiation time increased, the degree of damage to the solar cells intensified, and their damage threshold gradually decreased. Specifically, the cell surface exhibited varying degrees of melting pits and ablation of the rear electrode. From the perspective of damage mechanisms, the damage to the solar cells caused by the pulsed laser was primarily driven by thermal effects, including thermal melting damage and thermal stress damage. Compared to thermal melting, thermal stress damage had a more significant impact on the electrical performance of the solar cells.