41 research outputs found
Silicon carbide nanolayers as a solar cell constituent
Thin films of predominantly amorphous n-type SiC were prepared by non-reactive magnetron sputtering in an Ar atmosphere. A previously synthesized SiC was used as a solidstate target. Deposition was carried out on a cold substrate of ptype Si (100) with a resistivity of 2Ωcm. The Raman spectrum shows a dominant band at 982 cm-¹, i.e., in the spectral region characteristic for SiC. It was found that the root mean squareroughness varies from about 0.3 nm to 9.0 nm when the film thickness changes from about 2 nm to 56 nm, respectively. Transmission electron microscopy studies showed that SiC thin films consist predominantly of an amorphous phase with inclusions of very fine nanocrystallites. A heterostructure consisting of a p-type Si (100) and a layer of predominantly amorphous n-type SiC was fabricated and studie
Silicon solar cells based on pSi/nSi3N4 nanolayers
Thin films of Si3N4 were prepared by non-reactive magnetron sputtering in an Ar atmosphere. A previously synthesized Si3N4 was used as a solid-state target. Deposition was carried out on a cold substrate of p-Si (100) with a resistivity of 2 Ohm cm. The Raman spectrum of the deposited Si3N4 layers has been investigate
p Si n SiC NANOLAYER PHOTOVOLTAIC CELL
Thin films of amorphous SiC were prepared by non reactive magnetron sputtering in an Ar atmosphere. A previously synthesized SiC was used as a solid state target. Deposition was carried out on a cold substrate of p Si 100 with a resistivity of 2 Ohm amp; 61655;cm. The Raman spectrum shows a dominant band at 982 cm 1, i.e. in the spectral region characteristic for SiC. The film thickness determined from atomic force microscopy measurements was about 8 40 nm, the height of the structural units of the film was 1 2 nm, while the linear dimensions were of the order of tens of nanometers. The amorphous nature of SiC grown on the Si substrate is confirmed by the presence of the diffraction rings which indicate the absence of the dominant orientation of the prepared films. A heterostructure consisting of a p type Si 100 and a layer of amorphous n type SiC was fabricated and studied. The investigation of its electrical and photoelectric properties shows that the entire space charge region is located in Si. This is in addition confirmed by the spectral dependence of the p Si n SiC photo sensitivity. The barrier height at the p Si n SiC interface estimated from dark I V characteristics is of the order of 0.9 1.0 eV. Load I V characteristics of p Si n SiC amorphous nanolayer solar cells demonstrate under standard AM1.5 illumination conditions a conversion efficiency of 7.2
Kesterite thin films of Cu2ZnSnS4 obtained by spray pyrolysis
Thin films of Cu2ZnSnS4 CZTS were deposited using the spray pyrolysis method as relatively fast and vacuum free method. Obtained samples were analyzed using the X Ray Fluorescence, grazing incidence X Ray Diffraction and Raman Spectroscopy techniques. Analysis showed close to stoichiometry composition of the films with kesterite type structure but poor crystalline quality and possible existence of secondary phases. To improve the quality of the films, the as prepared layers were annealed in the presence of elemental Sn and S. Comparison of the results before and after annealing showed a strong improvement of the crystalline quality and a significant reduction of concentration of secondary phases of the films without significant change of composition. The measured optical band gap is equal to 1.52 and 1.55 eV in the as prepared and annealed films, respectively. The optical absorption coefficient is found to be gt; 10 4 cm
Silicon carbide nanolayers as a solar cell constituent
Thin films of predominantly amorphous n-type SiC were prepared by non-reactive magnetron sputtering in an Ar atmosphere. A previously synthesized SiC was used as a solidstate target. Deposition was carried out on a cold substrate of ptype Si (100) with a resistivity of 2Ωcm. The Raman spectrum shows a dominant band at 982 cm-¹, i.e., in the spectral region characteristic for SiC. It was found that the root mean squareroughness varies from about 0.3 nm to 9.0 nm when the film thickness changes from about 2 nm to 56 nm, respectively. Transmission electron microscopy studies showed that SiC thin films consist predominantly of an amorphous phase with inclusions of very fine nanocrystallites. A heterostructure consisting of a p-type Si (100) and a layer of predominantly amorphous n-type SiC was fabricated and studie