Improvement on the Performance of InP/CdS Solar Cells with the Inclusion of Plasmonic Layer of Silver Nanoparticles D. Ghosh & B. Ghosh & S. Hussain & B. R. Chakraborty & G. Sehgal & R. Bhar & A. K. Pal Received: 18 April 2014 /Accepted: 20 May 2014 # Springer Science+Business Media New York 2014 Abstract The effect of nano-Ag (n-Ag) plasmonic layer in InP/CdS solar cell structure was examined. An enhancement of short circuit current improving the overall cell efficiency was observed in InP/n-Ag/CdS cells. Location of the plas- monic layer in the above cell structure has been analyzed critically. The effect of introducing plasmonic layer on the overall performance of the cell has been studied in terms of the morphology, particle size distribution, optical absorption, I–V, C–V characteristics, and lifetime of the photo-generated car- riers. Secondary ion mass spectroscopy (SIMS) studies were carried out for investigating possible interface alloying. Keywords III–V semiconductor . Surface plasmon . Solar cell . Electron transport . SIMS PACS . 73.20.Mf . 72.20.Ee . 72.40.+w Introduction In order to increase the absorbance, structuring of solar cells with light trapping inside has become a very important issue. It is more pertinent to weak absorbers like silicon for fabricat- ing solar cells. For such system, it was possible to achieve light trapping by forming a wavelength-scale texture on the substrate and then depositing the thin-film solar cell on top. Despite the fact that a rough semiconductor surface would result in increased surface recombination, a large increment in photocurrent had been achieved in this way [1–6]. Thus, a search for new methods, to improve the performance of PV cells beyond what had been achieved so far, was on the hot anvil. In this respect, a new method for increasing the light absorption, that has emerged recently, is the use of scattering from noble metal nanoparticles excited at their surface plas- mon resonance. A consorted effort in improving photovoltaic (PV) cell efficiencies by utilizing a plasmonic layer in the cell structure was given by researchers [1–6]. Ib metals in nanocrystalline form showing localized plasmonic resonances (LPRs) have been thought of as an alternative to improve light trapping in silicon and organic solar cells. Atwater and Polman [1] dem- onstrated the ability to construct optically thick but physically very thin photovoltaic absorbers. This was achieved by using light trapping through the resonant scattering and concentra- tion of light in arrays of metal nanoparticles, or by coupling light into surface plasmon polaritons and photonic modes that propagate in the plane of the semiconductor layer. It was observed that a thin photovoltaic absorber layer (a few tens to hundreds of nanometers thick) might absorb the full solar spectrum. The effect of surface plasmons on silver nanoparticles for improving the efficiency of thin-film and wafer-based solar cells was reported by Pillai et al. [2]. Surface plasmons offered a promising way to improve the efficiency of thin-film solar cell structures. For directly textured silicon, the problem of increased recombination was avoided by this technique. Smaller metal particles provided maximum overall enhance- ment in the visible as well as the near-IR for solar cell applications. Possibility of integrating electronics and optics on the nanoscale utilizing surface plasmons (light-induced excitations of electrons on metal surfaces) was indicated by Polman [3]. Plasmonic effect of Au nanoparticles array D. Ghosh : B. Ghosh : R. Bhar : A. K. Pal (*) Department of Instrumentation Science, USIC Building, Jadavpur University, Calcutta 700 032, India e-mail: msakp2002@yahoo.co.in S. Hussain UGC-DAE CSR, Kalpakkam Node, Kokilamedu 603104, India B. R. Chakraborty : G. Sehgal CSIR-National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi 110 012, India Plasmonics DOI 10.1007/s11468-014-9741-0