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The thermolytic deposition of MoS2 nanolayers for use in Si solar cells is investigated for which a thin MoS2 nanolayer is grown on a crystalline Si substrate by the thermolysis method. The deposited MoS2 nanolayer and Si substrate are annealed and show a transition from an amorphous to a crystalline phase as the annealing temperature increases. The MoS2 (002) crystalline peak at 14.04° appears at an annealing temperature of 450 °C. The heterojunction interface of MoS2/np‐Si shows a mixed amorphous and crystalline phase. The Al/MoS2 has better Ohmic contact compared with Al/Si. The MoS2 nanolayer is introduced into the cell structure of a SiNx/a‐Si(n)/MoS2/np‐Si cell, the cell shows a photoconversion efficiency of 11.47%.

In this research, silicon solar cells with embedded silicon-on-insulation layer obtained via nitrogen ion beam implantation are investigated. The embedded layer acts as a minority carrier-blocking layer for the silicon solar cells, which results in the suppression of carrier recombination from the surface due to the formation of the silicon-on-insulation layer. This is achieved by integrating nitrogen ion implantation as a carrier reduction layer, which has a band offset asymmetry with silicon. The implantation is involved with the formation of surface defects by forming amorphous layers on Si surfaces. The electroluminescence images show that defects related to high energy nitrogen ion implantation are involved in the emission mechanism compared to low energy implanted nitrogen ion. From current-voltage analysis, the conversion efficiencies of nitrogen ion implanted cells are found lower than the reference cell, but the cell implanted with low energy nitrogen ion enhances the short circuit current density.

We investigated the effect of thermal annealing on the performances of Si solar cells. The Si solar cells were fabricated on p-type microtextured Si wafers using a standard cell fabrication process. The fabricated cells were annealed at 250 °C for 60, 80, and 90 min using a halogen lamp heater in N2 ambient. The annealed sample with a time of 60 min showed enhanced optical properties of light absorption, quantum efficiency, and minority carrier lifetime but did not show enhanced cell conversion efficiency. However, while the cell annealed for 90 min showed different optical properties, it showed the highest conversion efficiency of 17.35% compared to the reference cell of 17.14%, indicating the total recovery of the light soaking effect. We further analyzed the hydrogen-related chemical bonding structures for the dopant activation throughout hydrogen diffusion and the electroluminescence by a radiative recombination of a p–n junction.

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