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P-type CIGS (CuIn 1-x Ga x Se 2) thin films are electro-deposited on a p-type c-Si substrate with a galvanostatic mode to form CIGS(p)/c-Si(p) hetero-junction. The Ga content is varied up to x = 30%. The physical properties of formed CIGS films are characterized by XRD, SEM, EDS and UV–Visible spectroscopy. With x = 30%, we obtain a single chalcopyrite phase of CIGS with a tetragonal crystal structure, a high crystallinity, an orientation toward the (112) direction and a band gap energy of 1.40 eV. AM1.5 J-V performed on the CuI 0.7 G 0.3 Se 2 /c-Si hetero-junction reveals interesting photovoltaic parameters with an efficiency of 3.75%. In addition, using the energy diagram of the hetero-junction calculated with the Anderson model, we show that it could play a dual role when combined to a c-Si cell in a Ag–Al/c-Si(n+)/c-Si(p)/CIGS(p)/Al new architecture. Therefore, in addition to its interesting photovoltaic parameters, this hetero-junction can substitute the BSF. Image 1 • Highly polycrystalline CIGS film is electro-deposited on c-Si to form CIGS/c-Si hetero-junction. • AM1.5 J-V of the CuI 0.7 G 0.3 Se 2 /c-Si hetero-junction reveals interesting photovoltaic parameters. • Using the Anderson model, we show that the hetero-junction could play a dual in new architecture solar cell. [ABSTRACT FROM AUTHOR]

In semiconductor applications, surface and interface defects play a key-role on the electronic properties of the device. Several non destructive tools can be combined to characterize these defects. From microwave-Photo-Conductivity Decay (μW-PCD) measurements, one can access to an effective measurement of lifetime of minority carriers that characterizes both the surface and the bulk semiconductor material. On the other hand, Surface Photo-Voltage (SPV) is a powerful technique that gives credible bulk lifetime values from minority carriers' diffusion length measurements. In this paper, we use a nondestructive method by which we determine the surface and bulk defects densities in crystalline silicon wafers by combining μW-PCD and SPV tools using an adequate theoretical approach. We apply this method to three surface morphologies; a mirror-polished sample, a CP4 etched sample and a pyramidal textured sample. [ABSTRACT FROM AUTHOR]

In semiconductor applications, surface and interface defects play a key-role on the electronic properties of the device. Several non destructive tools can be combined to characterize these defects. From microwave-Photo-Conductivity Decay (μW-PCD) measurements, one can access to an effective measurement of lifetime of minority carriers that characterizes both the surface and the bulk semiconductor material. On the other hand, Surface Photo-Voltage (SPV) is a powerful technique that gives credible bulk lifetime values from minority carriers' diffusion length measurements. In this paper, we use a nondestructive method by which we determine the surface and bulk defects densities in crystalline silicon wafers by combining μW-PCD and SPV tools using an adequate theoretical approach. We apply this method to three surface morphologies; a mirror-polished sample, a CP4 etched sample and a pyramidal textured sample. [ABSTRACT FROM AUTHOR]

An intermediate complex approach coupled with a preheating strategy are used to grow mixed-cation FA 1-x Cs x PbI 3 perovskite films in ambient air. This was achieved through an effective PbI 2 conversion and the elimination of the detrimental moisture effect, which was ensured by the formation of an intermediate complex along with the rapid solvent evaporation induced by the preheating of the substrate and/or precursor solutions. Moreover, it is found that the control of [CsI]/[FAI] ratio clearly influences the crystallization of the α-perovskite phase and could effectively inhibit the growth of non-perovskite crystallites, which stabilizes the photoactive α-phase. X-ray diffraction analyses indicate that a change in crystal orientation from (100) to (111) direction occurs for 35% CsI added in the perovskite precursor, inducing a decrease in the band gap energy. Moreover, the stability is significantly improved in the (111) direction, in agreement with computational results obtained in literature. • Mixed-cation FA-based perovskite films are prepared in fully-ambient air. • XRD analysis demonstrates a crystal orientation change from (100) to (111) direction for 35% Cs concentration. • The control of the amount of Cs in FAPbI 3 promotes the stabilization of the α-phase. • A correlation between structural evolution, band gap tuning, and stability improvement is shown. [ABSTRACT FROM AUTHOR]