Electrical and impedance spectroscopy analysis of sol-gel derived spin coated Cu2ZnSnS4 solar cell

Abstract

We carried out electrical and impedance studies on solution derived Al:ZnO/ZnO/CdS/Cu2ZnSnS4/Mo/Glass multilayered solar cell structures to understand their impact on photovoltaic performance. The Cu2ZnSnS4 layer is synthesized on a molybdenum (Mo) coated soda lime glass substrate as an absorber and characterized intensively to optimize the absorber physical properties. The optimized Cu2ZnSnS4 is p-type with 5.8 × 1017 cm−3 hole carrier concentration. The depletion width of the junction is around 20.5 nm and the diffusion capacitance is ∼35.5 nF for these devices. We observed relatively large minority carrier life time ∼23 μs for these structures using open voltage decay analysis. The measured Cu2ZnSnS4/MoS2 and Cu2ZnSnS4/CdS interface resistances are 7.6 kΩ and 12.5 kΩ, respectively. The spatial inhomogeneities are considered and the corresponding resistance is ∼11.4 kΩ. The impedance measurements suggest that in conjunction with series resistance ∼350 Ω, the interface and spatial inhomogeneity resistances also give a significant contribution to the photovoltaic performance.

On the Importance of Joint Mitigation Strategies for Front, Bulk, and Rear Recombination in Ultrathin Cu(In,Ga)Se2 Solar Cells

“…In the literature, C1-R1 is associated with defects levels in the absorber layer bulk. 68,76,77 The C1-R1 connection is present in all circuits, meaning that in our studied devices, the passivation strategies implemented were not able to mitigate such defect level. The C2-R2 is only absent for the device without the Al2O3 layer, thus we attribute the C2-R2 to a frequency response of the dielectric layer.…”

Partial substitution of the CdS buffer layer with interplay of fullerenes in kesterite solar cells

“…7a) represents, semicircles that size changes with the voltage. These semicircles fits with equivalent circuit composed by a series resistance followed by a certain number of loops with a capacitor and a resistance 36,37 , as illustrated in the Fig. 7b.…”

Structural evolution of chemically deposited binary stacks of Sb 2 S 3 ‐CuS to phase‐pure CuSbS 2 thin films and evaluation of device parameters of CuSbS 2 /CdS heterojunction

“…These data are used to derive Nyquist plots, which are shown in Figure A and B. Further, these Nyquist plots are simulated using the resistance‐capacitance equivalent circuit as shown in Figure C . Here, series resistance R s accounts for combined bulk material resistance and contact resistances.…”