Chemical-bath ZnO buffer layer for CuInS2 thin-film solar cells

A. Ennaoui, M. Weber, R. Scheer, H. J. Lewerenz

Research output: Contribution to journalArticle

105 Citations (Scopus)


ZnO buffer layers were grown by a chemical-bath deposition (CBD) in order to improve the interface quality in p-CuInS2 based solar cells, to improve the light transmission in the blue wavelength region, but also as an alternative to eliminate the toxic cadmium. The process consists of immersion of different substrates (glass, CIS) in a dilute solution of tetraamminezinc II, [Zn(NH2)4]2+, complex at 60-95°C. During the growth process, a homogeneous growth mechanism which proceeds by the sedimentation of a mixture of ZnO and Zn(OH)2 clusters formed in solution, competes with the heterogeneous growth mechanism. The mechanism consists of specific adsorption of a complex Zn(II) followed by a chemical reaction. The last process of growth results in thin, hard, adherent and specularly reflecting films. The characterization of the deposited CBD-ZnO layers was performed by X-ray diffraction (XRD), optical transmittance, scanning electron microscopy, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The as-deposited films on glass show hexagonal zincite structure with two preferred orientations (1 0 0) and (1 0 1). High optical transmittance up to 80% in the near-infrared and part of the visible region was observed. The low growth rate of the films on CIS suggests an atomic layer-by-layer growth process.The device parameters and performance are compared to heterojunction with a standard CdS buffer layer.

Original languageEnglish
Pages (from-to)277-286
Number of pages10
JournalSolar Energy Materials and Solar Cells
Issue number1-4
Publication statusPublished - 13 Jul 1998


  • Chemical bath
  • CuInS thin film
  • ZnO buffer layer

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Renewable Energy, Sustainability and the Environment
  • Surfaces, Coatings and Films

Fingerprint Dive into the research topics of 'Chemical-bath ZnO buffer layer for CuInS<sub>2</sub> thin-film solar cells'. Together they form a unique fingerprint.

  • Cite this