Diamond-like carbon films were electrodeposited on n-Si substrate to realize an n-Si/DLC PV structure. The films thus obtained were characterized by FESEM, XPS, FTIR, and Raman studies. Solar cell characteristics were also investigated critically. Maximum efficiency of 3.7% was obtained for the best n-Si(100)/DLC structure. Carrier life time was obtained from decay measurement. It was observed that photoinduced charge separation in n-Si(100)/DLC structure was associated with an increase in the dielectric constant and a decrease in the device resistance. The process, being reproducible, cheap, and scalable, involving significantly less process steps, is likely to usher a new hope to the current competitive scenario of PV technology. 1. Introduction During the last two decades diamond-like carbon (DLC) films were studied extensively due to their fascinating and exotic properties. Reports on the microstructural, mechanical, electrical, optical, and thermal properties of hydrogenated amorphous carbon films have poured in the literature [1–7]. Along with these properties and being a p-type material, DLC films are emerging as a potential candidate for photovoltaic application [8–11]. Although different carbon nanostructured materials showed promises in this regard, difficulty in depositing diamond-like carbon films directly on silicon substrates [12, 13] adopting cost-effective, scalable, and reproducible technique deterred the use of such carbon materials for device application. In recent times, Paul et al. [14] studied hydrophobic characteristics of such DLC films deposited on SnO2-coated substrates while Gupta et al. [15] reported the dependence of field emission properties of DLC films electrodeposited at different voltage. Although there has been intense research activity on the use of carbon nanomaterials in areas such as electronics and photonics [16], the use of carbon in various forms as the active layer material in PV is still largely unexplored. Moreover, the use of carbon nanostructured materials would favour the use of green technology in PV cell manufacturing areas. Recent reports indicated the use of carbon materials mainly in photovoltaics as acceptors in polymer-based solar cell or as transparent electrodes [8] and only recently as the main active layer components in polymer free solar cells [9, 17, 18]. In this paper, the viability of utilizing electrodeposited DLC films on n-Si (100) for PV application is explored. 2. Experimental Details Diamond-like carbon films (DLC) were synthesized by electrolysis using acetic acid (CH3COOH) and
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