• Bär, M.; Barreau, N.; Couzinié-Devy, F.; Pookpanratana, S.; Klaer, J.; Blum, M.; Zhang, Y.; Yang, W.; Denlinger, J.D.; Schock, H.-W.; Weinhardt, L.; Kessler, J.; Heske C.: Nondestructive depth-resolved spectroscopic investigation of the heavily intermixed In2S3/Cu(In,Ga)Se2 interface. Applied Physics Letters 96 (2010), p. 184101/1-3

10.1063/1.3425739

Abstract:
The chemical structure of the interface between a nominal In2S3 buffer and a Cu(In,Ga)Se2 (CIGSe) thin-film solar cell absorber was investigated by soft x-ray photoelectron and emission spectroscopy. We find a heavily intermixed, complex interface structure, in which Cu diffuses into (and Na through) the buffer layer, while the CIGSe absorber surface/interface region is partially sulfurized. Based on our spectroscopic analysis, a comprehensive picture of the chemical interface structure is proposed.