Current transport in Cu(In,Ga)S2 based solar cells with high open circuit voltage-bulk vs. interface

Saoussen Merdes, Benjamin Johnson, Rodrigo Sáez-Araoz, Ahmed Ennaoui, Joachim Klaer, Iver Lauermann, Roland Mainz, Alexander Meeder, Reiner Klenk

Research output: Chapter in Book/Report/Conference proceedingConference contribution

14 Citations (Scopus)


In a previous work, Cu(In,Ga)S2 thin films prepared by rapid thermal sulfurization of metallic precursors yielded solar cells with efficiencies reaching 12.9%, a short circuit current density of 22.3 mA/cm 2 and open circuit voltages up to 850 mV. However, the fill factor was close to, but typically did not exceed 70%. In this contribution we report on the role of junction formation by chemical bath deposition on these parameters. Concentrations in the bath and deposition times were varied. A comparison is made between CdS and Zn(S,O) buffer layers. The influence of the incorporated gallium on surface properties was investigated by ultraviolet photoelectron spectroscopy (UPS) for the valence band edge and near edge X-ray absorption fine structure (NEXAFS) for the conduction band edge. Even in our best cell (13.1%) the activation energy of the saturation current is found to be still smaller than the band gap. High diode ideality factors and voltage dependent current collection prevent higher fill factors.

Original languageEnglish
Title of host publicationMaterials Research Society Symposium Proceedings
Number of pages6
Publication statusPublished - 2010
Externally publishedYes
Event2009 MRS Spring Meeting - San Francisco, CA
Duration: 13 Apr 200917 Apr 2009


Other2009 MRS Spring Meeting
CitySan Francisco, CA


ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanical Engineering
  • Mechanics of Materials

Cite this

Merdes, S., Johnson, B., Sáez-Araoz, R., Ennaoui, A., Klaer, J., Lauermann, I., Mainz, R., Meeder, A., & Klenk, R. (2010). Current transport in Cu(In,Ga)S2 based solar cells with high open circuit voltage-bulk vs. interface. In Materials Research Society Symposium Proceedings (Vol. 1165, pp. 179-184)