Growth and Studies on Indium and Zinc Based Buffer Layers for Development of Photovoltaic Solar Cell Development
Abstract
Thin film solar cells based on chalcopyrite semiconductors have reached ahigh level performance over the last years both for laboratory scale cellsand commercial products. Research on CIGS-based photovoltaic cell isdeveloping towards the use of wide band-gap and non-toxic materials toreplace the cadmium sulphide buffer layer, which is used as an interfacialbuffer layer. A non-toxic photovoltaic technology poses fewer issues thana toxic technology and would clearly be a superior choice provided andother aspects are the same. Promising alternative materials used indifferent laboratories are mainly (sulfides, selenides and oxides) Zn andIn based buffer layers. These materials demonstrated their potential tolead high efficiency solar cells and modules comparable with standardchemical bath deposited (CBD) CdS. We have investigated the physicalproperties of alternative buffer layer materials (i.e., In2S3, ZnS, ZnMgO)employing different deposition techniques aiming to replace the CBD-CdSlayer in CIGS solar cells. The physical properties of such materials arestrongly depending on the deposition methods employed and processparameters maintained during the growth of the films. These properties canbe controlled and reproduced by precisely modulating of depositionparameters.
14/03/2011 at 4:00 pm
Dr. R. Palit, TIFR, Mumbai
NP Seminar
Lecture Hall Block A, Institute of Physics
Document Date:
High Resolution Gamma Spectroscopy for Investigation of Exotic Nuclear Shape
Jet properties in pp and its modification in nuclear matter
Abstract
Jets are manifestation of hard scatterings of partons and its understanding in pp involves the partondistribution functions, the QCD-hard scattering processes and the long distance fragmentation phenomena.Therefore, jets can be used to study the parton level kinematics. Intrinsic transverse momentumof partons and the subsequent gluon radiations prior to hard scatterings [1], give rise to acoplanarityof dijets, depending on the Q2 of hard scatterings and the center of mass energy of collisions. Multiplescatterings of the hard scattered partons in cold nuclear matter may incorporate a modi cation of jetstructure.Two quantities commonly used to characterize the properties of jets are (i) jt, the transverse momentumof the jet fragments relative to the jet axis and (ii) kt, the transverse component of the momentumof the hard scattered partons. A measurement of the jet parameters, phj2t i and phk2t i [2] at STAR inpp collisions at ps = 62.4, 200 and 500 GeV using di-hadron correlation techniques is presented in widekinematics rage. 0 (Et = 6.5 to 18.5 GeV) and charged tracks (pt = 3.0-8.5 GeV/c) are used as triggerparticles in this analysis. A comparison of the jet parameters for pp and dAu (at various centralities) atps = 200 GeV will be presented.References[1] R.P Feynman, R.D. Field, and G.C. Fox, Phys. Rev. D18 3320(1978).[2] S.S. Adler et al., Phys. Rev. D74 072002(2006).
