Extended Data Fig. 3: Scaling up the fabrication method.
From: A fabrication process for flexible single-crystal perovskite devices

a, Freestanding transferred single-crystal MAPbI3 thin films fabricated by soft polymer masks and corresponding bulk substrates. b, A large bulk substrate (left) that is used to epitaxially grow the single-crystal MAPbI3 thin film (left) and a transferred single-crystal MAPbI3 thin film using a rigid copper foil (20 μm thick) as the mask (right).