The investigation of stability of n-CdS/p-Cu₂S solar cells prepared by cold substrate method

In this study, two different n-CdS/p-Cu₂S solar cells were prepared by evaporating Cu at different substrate temperatures (200 K and 300 K) by vacuum evaporation method on a single crystal CdS semiconductor. Field emission scanning electron microscope images showed that the Cu layer obtained at a temperature of 200 K was composed of nanoparticles in accordance with the soliton growth mechanism. Cu film thickness was determined as 395 ∓ 0.76 nm at 300 K substrate temperature and 187 ∓ 0.45 nm at 200 K substrate temperature. The current–voltage (I–V) and capacitance–voltage (C–V) characteristics of the solar cells were examined for 12 weeks in dark and light environments. Open-circuit voltage (V _oc), short-circuit current (I _sc), maximum power (P _max), filling factor and efficiency (η) were calculated from I–V measurements. For the prepared solar cells, the highest efficiency value was obtained in the 7th week (η= 0.1360) at 200 K substrate temperature, while it was obtained in the 5th week (η = 0.0384) at 300 K substrate temperature. From C–V measurements, donor density (N _d) and barrier potential (V _bi) were calculated. The solar cell produced at 200 K substrate temperature has higher donor density (1st week 2.99 × 10¹⁶ cm⁻³) and barrier potential values (12th week 0.411 V). At the end of the 12-week period, the deterioration rate of solar cells created at 200 K and 300 K substrate temperatures was 51% and 94%, respectively. (paper)