Fig. 1. Characterization of atomically thin 2D layered pentacene samples.
a Optical microscope image of the sample used for measurements. The scale is 80 μm. b Zoomed-in atomic force microscopy (AFM) image of the dashed square region in a, showing the actual measured thicknesses of WL and 1L pentacene. The scale is 2 μm. c Schematic diagram showing the orientation and alignment of pentacene molecules in WL and 1L over h-BN and a SiO2/Si substrate. d Measured PL spectra from WL and 1L samples at room temperature