Electrodeposited diamond-like carbon (DLC) films on n-Si(100) substrates for photovoltaic application

Synthesis of n-Si/diamond-like carbon (DLC) bi-layer films was realized by depositing DLC films on n-Si (100) substrate by a simple electrodeposition technique using acetonitrile (CH3CN) as the electrolyte. The films were characterized by Field Emission Scanning Electron Microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), Fourier Transformed Infrared spectroscopy (FTIR) and Raman studies. Solar cell characteristics were investigated critically. Open circuit voltage (Voc) and short circuit current density (Jsc) obtained for the best n-Si (100)/DLC structure were 335 mV and 9.6 mA/cm2, respectively, corresponding to a total conversion efficiency of η= 1.65%. Open circuit photovoltage decay measurement was carried out to determine the carrier lifetime. Photoinduced charge separation in the n-Si (100)/DLC structure could be associated with an increase in the dielectric constant and a decrease in the device resistance. The process is cheap, reproducible and scalable, involving significantly lesser process steps. This is likely to usher in a new hope to the current competitive scenario of photovoltaic (PV) technology.