The effect of grain boundary misorientation angle on selenium diffusion in CdSexTe1-x solar cells

The effect of grain boundary (GB) misorientation on selenium (Se) diffusion and bandgap grading in cadmium telluride (CdTe) devices incorporating a CdSexTe1-x alloy has been investigated using high-resolution cathodoluminescence (CL) and electron backscatter diffraction (EBSD). Using CL, we map the bandgap variations and the Selenium concentration across the absorber. EBSD provides corresponding information on grain boundary orientation from the same cross-section of the device. This correlative analysis reveals that larger grain boundary misorientation angles promote greater Se diffusion, resulting in a lower bandgap (BG) in grains associated with this type of grain boundary.<p></p>