Figure 6. Structure-model derived from the flipped device. The insulating varnish is neglected in the structure-model for simplification. The Cu2S-crystallites (brown ellipses) have a narrow band-gap (see band-model in the upper right corner) and play a vital role for the bipolar injection mechanism

From

Hello Future! Printed Electronics as a Hands-On Experiment for Science Teaching

Lena Halbrügge, Amitabh Banerji, Sven Rösler

World Journal of Chemical Education. 2021, 9(4), 104-110 doi:10.12691/wjce-9-4-2