All silicon carbide based p-i-n photovoltaic solar cells with conversion efficiency enhanced by detuning the composition ratio of i-SixC1−x layer

All silicon carbide (Si_xC_1-x) based p-i-n photovoltaic solar cells (PVSCs) is demonstrated by growing the non-stoichiometric Si-rich Si_xC_1-x films with plasma enhanced chemical vapor deposition (PECVD). With decreasing the CH₄/(CH₄+SiH₄) fluence ratio from 50% to 30%, the Si/C composition ratio of the Si-rich Si_xC_1-x film increases from 1.99 to 2.78. For the Si-rich Si_0.74C_0.26 film, the broadband absorption spectrum shows the highest optical absorption coefficient of up to 1.9×10⁵ cm^-1. The ITO/p-Si_xC_1-x/i-Si_xC_1-x/n-Si_xC_1-x/Al solar cell provides the conversion efficiency and filling factor enhancing from 1.41% to 2% and from 23.1% to 25.6%, respectively, by enlarging the Si/C composition ratio of i-Si_xC_1-x layer from 1.99 to 2.78.