Extended Data Fig. 7: Performance optimization of the mixture-1.0 perovskite LED.
From: Perovskite light-emitting diodes with external quantum efficiency exceeding 20 per cent
a, Cross-sectional SEM image of a perovskite LED device with a PMMA blocking layer. b, c, AFM topography image (b) and thickness measurement (c) of the optimized PMMA layer. The differently coloured lines show multiple test results from the same sample. d, e, Optimizing device performance by tuning the thickness of the PMMA layer (d) and the amount of MABr additives in the perovskite precursor (e).
