Unraveling the effects of a GeSe BSF layer on the performance of a CuInSe₂ thin film solar cell: a computational analysis

Abstract

In this work, a dual-heterojunction (DH) thin film solar cell of notable efficiency has been designed and simulated where p-type CuInSe2 (CIS) has been employed as the base layer in combination with an n-type CdS window and a p + -type GeSe back surface field (BSF) layer. The influences of each layer have been revealed using the SCAPS-1D simulator. While the n-CdS/p-CIS single heterojunction (SH) structure acting alone has been found to be resulted with 24.86% of photoconversion efficiency (PCE) with the JSC = 42.80 mA/cm2, VOC = 0.70 V, and FF = 83.44%, an enhancement to PCE of 30.52% is observed with the corresponding JSC of 44.10 mA/cm2, VOC of 0.86 V, and FF of 80.30% owing to the addition of GeSe as BSF layer in the proposed structure with optimized parameters. Because of the enormous built-in potential of the CIS/GeSe interface, increased VOC mostly contributes to the efficiency enhancement. These findings suggest that the CIS absorber layer with GeSe BSF layer is a promising choice for solar energy harvesting in the near future.

Design of an Efficient AgInSe2Chalcopyrite‐Based Heterojunction Thin‐Film Solar Cell

“…The enhancement of PCE is primarily owing to the annex of J SC and V OC which result from the enhanced built‐in potential developed at the AgInSe 2 /MoS 2 junction that reduces saturation current by reducing surface recombination velocity due to passivation of the surface‐trapping centers as well as reduction of the photo‐generated carriers recombination at the boundary region by back surface field of the device. [ 51–53 ]…”

“…The enhancement of PCE is primarily owing to the annex of J SC and V OC which result from the enhanced built-in potential developed at the AgInSe 2 /MoS 2 junction that reduces saturation current by reducing surface recombination velocity due to passivation of the surface-trapping centers as well as reduction of the photo-generated carriers recombination at the boundary region by back surface field of the device. [51][52][53] The quantum efficiency (QE) is a ratio that can be found by comparing the charge carrier with the total number of ingress photons. [48,49] The change of QE with respect to wavelength has been cultivated at different thickness of the absorber layer as delineated in Figure 7b.…”

Design and Simulation of a High‐Efficiency CuInS2Thin‐Film Solar Cell with a Thin CIS Current Augmenter

“…Thin-film photovoltaic (PV) devices have drawn more focus, due to their low price, stability, adaptability, and satisfactory power conversion efficiency (PCE). [1] Specifically, chalcopyrite semiconducting compound-based devices have gained plenty of attention in the era of thin-film solar cells, making them the most competitive to wafer-based Si solar cells due to their spectacular efficiency. CuInGaSe 2 (CIGS), the most extensively studied chalcopyrite compound, has so far attained an experimental PCE of 19-23%, [2][3][4][5] while its theoretical PCE reached 47%, utilizing CuGaSe 2 (CGS) as a back surface field (BSF) layer.…”

“…CdS is the most widely used semiconductor as a window layer due to its broad bandgap of 2.4 eV, high carrier concentration, strong transmission, and exceptional stability under incoming light and absorption coefficient in the order of 10 4 cm À1 . [1,19] Moreover, the simulation uses a BSF layer made of the well-known semiconductor molybdenum disulfide (MoS 2 ), which belongs to the transition metal dichalcogenide group and has a hexagonal structure. The MoS 2 has a direct bandgap of 1.62 eV with strong absorption coefficient of 10 6 cm À1 that makes it a perfect candidate as a BSF layer.…”

“…CuInSe 2 is also a ternary chalcogenide compound that is part of the same I-III-VI family like CuInS 2 . [1] The CIS has a direct bandgap of 1.1 eV with the cutoff wavelength of around 1127 nm and a satisfactory absorption coefficient of 10 5 cm À1 . [22] In addition, CIS even now shows experimental PCE of 15-19.2% [23,24] and numerical PCE of 14-30.52%, [1,25] when acting as a single absorber.…”