Regensburg 2019 – wissenschaftliches Programm
HL 45.18: Poster
Donnerstag, 4. April 2019, 18:30–21:00, Poster E
Properties of In2S3:V-Based Intermediate Band Solar Cells — •Tanja Jawinski1,2, Rainer Pickenhain1, Leonard Wägele2, Michael Lorenz1, Roland Scheer2, Marius Grundmann1, and Holger von Wenckstern1 — 1Universität Leipzig, Halbleiterphysik, Germany — 2Universität Halle, Photovoltaik, Germany
To overcome the Shockley Queisser limit of single junction solar cells an intermediate band (IB) can be introduced in wide band gap materials in order to reduce thermalization . Absorption of photon energies smaller than the band gap can generate transitions from the valence band to the IB and from the IB to the conduction band. Theoretical calculations suggest that In2S3 hyper-doped with vanadium is a suitable candidate for realization of such an IB solar cell.
Intrinsic V-doped and undoped In2S3 layers are grown by physical co-evaporation of the elements. Heterostructure pin solar cells are formed using n-ZnO:Al and p-ZnCo2O4 grown by radio-frequency sputtering and pulsed laser deposition, respectively . Furthermore, we grew In2S3 and In2S3:V epitaxially on p-Si wafers to improve structural properties of the samples. The samples are investigated using a combination of tuneable IR and VIS lasers allowing simultaneous excitation with multiple photons of well defined sub-band gap energies for photocurrent measurements. We compare undoped and V-doped samples with varying doping concentrations and find a small increase in sub-band gap photocurrent for samples with highest doping concentrations of 1.1 at%.  Luque and Martí, Phys. Rev. Let., 78(26),1997  Jawinski et al., Phys. Stat. Sol. A, 215(11), 2018