CIGS solar cell devices on steel substrates coated with Na containing AlPO4

Flexible copper indium gallium diselenide (CIGS)-based solar cells are developed on stainless steel (STS) substrates covered with an insulating layer. The Na containing AlPO4 (“Na-AlPO4”) material is processed using the slot-die coating method. The coated film is analyzed using various spectroscopic methods including scanning electron microscopy, energy dispersive X-ray spectrometry, transmission electron microscopy, secondary-ion mass spectrometry, X-ray diffraction, and 3D profiler. The characteristics of the solar cells fabricated on these insulating films are also evaluated. The application of the Na-AlPO4 layer on the STS substrates is compared with the electrical performance of the CIGS solar cells fabricated on metal foil. Although the insertion of the insulating layer does not influence the formation of the CIGS film and solar cell performance, a better uniformity in the current-voltage curve is obtained.