We investigate local electronic properties of cadmium telluride solar cells using electron beam induced current (EBIC) measurements with current-collecting patterned contacts. EBIC measurements are performed with a spatial resolution as high as ≈20 nm both on the top surface and throughout the cross-section of the device, revealing an enhanced carrier collection in the vicinity of grain boundaries. Furthermore, we measure local current-voltage characteristics using contacts with dimension both larger (≈5 µm × 10 µm) and smaller (≈1 µm × 1 µm) than the device thickness (≈4 m), finding that the value of local open-circuit voltage is also larger near grain boundaries.
Citation: Solar Energy Materials and Solar Cells
Pub Type: Journals
solar cell, thin film, CdTe, grain boundary, electron beam induced current, EBIC, cross section, focused ion beam, FIB