Large‐Scale, Panchromatic Structural Color Manipulation via Thermal Trimming

Abstract Structural color allows for a vibrant pigment‐free coloration for many potential applications. But now, it is still hindered in practice with crucial issues including complicated fabrication, defective and static appearance. Post‐trimming is proposed for defect‐free and controllable color manipulation after fabrication, which is significant for structural color in practical applications. Till now, most present post‐trimming methods are inhibited due to limited trimming range. Here, a simple and practical strategy supporting wafer‐scale and panchromatic structural color post‐trimming is proposed. By simply controlling a thermal oxidation process, the proposed device can be tuned precisely from red to blue covering the whole visible region. Moreover, a “burn to read” and “burn after reading” structural color is also demonstrated for the first time. Partial thermal oxidation can reveal the encoded information (i.e., “burn to read”) and complete oxidation will erase the encoded information (i.e., “burn after reading”) owing to a transition from a broadband Salisbury screen‐like cavity to a Gires‐Tournois‐like cavity. The trimming technology is further expanded by using an ns‐pulsed laser and on a flexible substrate, which implies this simple and reliable technology may promote the advancement and applications of structural color in security imaging, anti‐counterfeiting, color display, and printing.