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This manuscript reports on an analytical study required to determine and enhance the effect of the high–low junction based back surface field (BSF) of thin n-CdS/p-SiGe/p + -BaSi2 heterojunction solar cell. A 0.3 µm thick BSF layer made of extensively available and low-cost barium silicide (BaSi2) is introduced into the basic SiGe solar cell for the first time. SCAPS-1D simulator is employed to analyze different parameters such as open circuit voltage (Voc), short-circuit current density (Jsc), fill factor (FF), quantum efficiency (QE) and conversion efficiency ( η ) of the device. The SiGe absorber layer thickness is varied from 2 to 50 µm to analyze the device performance, however optimum results are observed between 10 and 15 µm. The BSF BaSi2 layer thickness changing from 0.1 to 0.8 µm to check the viability of device for optimal efficiency. The present structure anticipates an efficiency of 17.05% for BSF layer thickness of 0.8 µm. In addition, the use of SiGe earth abundant material instead of CIGS having rare earth metals indium and gallium, reduces the overall fabrication cost of the solar cell.

In this research work BaPr x Fe 2-x O 4 (x = 0.0, 0.025, 0.05, 0.075, 0.10) spinel ferrites have been synthesized successfully by sol-gel technique. X-ray diffraction analysis confirmed the fcc spinel phase of the synthesized samples. All the samples showed inhomogeneous grain size distribution observed through scanning electron microscopy (SEM).Temperature dependence normalized AC susceptibility and Curie temperature studies revealed that BaFe 2 O 4 exhibited multidomain (MD) structure with high Curie temperature. On the other hand, multidomain to single domain (SD) transitions occurred when the praseodymium is substituted into barium spinel ferrites. Narrow loops showed the soft nature of ferrites and it was confirmed from magnetic properties of the prepared samples. Decreasing trend of saturation magnetization and remanence was observed with the substitution of praseodymium contents. Coercivity and anisotropy constant both enhanced with the praseodymium concentration. The above-mentioned parameters revealed that the synthesized spinel ferrites might be useful for the of high-density magnetic recording applications.

This paper presents the development of a physically based solar cell simulation using the Silvaco-TCAD simulator. Simulations were performed on a Si based solar cell with antireflection coating (ARC), without ARC and ARC with back surface field. Single layer SiO 2 ARC was used and its effect on each solar cell was analysed. The effect of BSF and AR coatings on the performance of the solar cells were performed using AM 1.5 G. The Si solar cell with SiO 2 AR coating and BSF cell demonstrated increased efficiencies of about 154%, and 77%, respectively, compared with the non-ARC BSF Si solar cell. The addition of the BSF initiated 43% improvement in the efficiency of Si solar cells, compared with 5.9% of the SiO 2 (AR) coated non-BSF Si solar cell. The designed model indicate the potential of combining the SiO 2 AR coating with BSF in the improved fabrication of high-efficiency, low-cost Si solar cells.

This work investigates the radiation tolerance of c-Si solar cells under electron energy of 9 MeV with fluence of 5.09×1016 cm−2. The solar cells were fabricated and characterized before and after electron irradiation through current-voltage (I-V), capacitance-voltage (C-V), and frequency dependent conductance (Gp) measurements. The results revealed that all the output parameters such as short circuit current (Isc), open circuit voltage (Voc), series resistance (Rs), and efficiency (η) were degraded after electron irradiation. Capacitance-Voltage measurements show that there is a slight decrease in the base carrier concentration (ND), while a small increase in depletion layer width (WD) was due to an increase in the base carrier concentration. Enhancements in the density of interface states (Nss), and trap time constant (τ) have been observed after electron irradiation. The results has revealed that back surface field (BSF) solar cell with front surface passivation (FSP) presented lowest efficiency degradation ratio of 11.3% as compared to 15.3% of the solar cell without FSP. The subsequent annealing of irradiated Si solar cell devices revealed that the Si solar cell with FSP demonstrated high efficiency recovery ratio of 94% as compared to non-FSP solar cell.

This work focuses on the performance of Al-doped CdS quantum dot (QD)/TiO2 solar cells. The devices were analyzed through current-voltage and capacitance-voltage measurements. It was observed from the analysis of absorption spectra that TiO2 nanowires improve the absorption of light of Al doped CdS QDs both in visible and near infrared (NIR) range. Current-voltage characteristics curve of Al doped CdS/TiO2 at different illuminations show that decrease in illumination (from 100 to 5 mW/cm2), affects the voltage and current correspondingly. Power-voltage curve at various intensities of light indicates that power of the solar cell increases with the increase of the bias voltage and reaches its maximum value at each value of light illumination intensity. The peak value of power at maximum illumination is 35 µW at 0.20 V and with decreasing illumination the peak value decreases. Capacitance-voltage measurements reveal that by increasing the bias voltage from −2.0 V to 0 V, the capacitance voltage indicates the rising trend. However, at 5 kHz and 10 kHz frequencies, it was observed that a marginal increase of capacitance was noticed with exceeding bias voltage. The results revealed that subsequent addition of the TiO2 nanowires significantly improved the output performance of QDSSC.

Projection operator techniques modified to handle orthogonal states and extension of potential in sudden approximation to non-identical nuclei are used to extract resonance parameters and resonant states. Application to 8Be, α-12C and α-16O systems show good agreement with experimental work.

Back surface field (BSF) (n+–p–p+) silicon (Si) solar cells were fabricated with and without TiO2 or SiO2 single layer antireflection (SLAR) coatings. The two cell types were obtained with non-texturized surfaces and compared with each other, as well as with an as-grown Si solar cell. The effective aluminium–BSF was fabricated through a simple thermal evaporation and alloying (850 °C, 50 min) technique. The effect of BSF and AR coatings on the performance of the solar cells were characterized through electrical (AM 1.5 G, 100 mW/cm2), optical, and morphological measurements. The BSF Si solar cells with TiO2 and SiO2 AR coatings and without AR coatings demonstrated increased efficiencies of about 168%, 115%, and 50%, respectively, compared with the as-grown Si solar cell. The addition of the TiO2 (AR) layer initiated 24% improvement in the efficiency of the monocrystalline BSF Si solar cells, compared with 6.9% of the SiO2 (AR) coated BSF Si solar cell. The results indicate the potential of combining the TiO2 SLAR coating with BSF in the improved production of high-efficiency, low-cost Si solar cells.

Reduced surface reflectance and enhanced light trapping is required by any high efficiency solar cell. Anisotropic etching was done on silicon (1 0 0) by using tetramethyl ammonium hydroxide TMAH, (CH3)4NOH, solution at 85 °C. Process variables considered were solution concentration and time proposed by response surface methodology (RSM). An effective surface texture was resulted with reflectance less than 8% without antireflection coating. The antireflection mechanism was also co-related with the etch rate of Si. Optimized values predicted by RSM for time and TMAH concentration were 5 min and 3.50% respectively. The technique and optimization of parameters by using response surface methodology (RSM) could be valuable in the texturization process for high-efficiency Si solar cells.