Dense CIGS films obtained by blending submicron‐sized particles with nanoparticle suspensions using a non‐vacuum process

The difficulty in densification easily occur in CIGS thin film absorber fabrication using the non‐vacuum process. A novel process is developed in this study to achieve dense, crack‐free and large‐grained CIGS films by blending submicron‐sized particles with nanoparticle suspensions. The addition of slow‐sintering submicron‐sized particles to the nanoparticle suspensions effectively inhibits crack generation and small grain development in the film microstructure. The submicron‐sized particles addition to nanoparticle suspension effect on the microstructure and electrical properties are investigated using scanning electron microscopy, X‐ray diffraction, UV‐Vis‐NIR, Raman spectroscopy and Hall‐effect analyzer. A homogeneous dense microstructure with a large grain size and good electric properties can be obtained as the submicron‐sized particles ratio to nanoparticles approaches 3:7.