All-Screen-Coatable Photo-Thermoelectric Imagers for Physical and Thermal Durability Enhancement

Carbon nanotube (CNT) film photo-thermoelectric (PTE) imagers are suitable for non-destructive inspection techniques owing to their functionalities. Simultaneously, their practical application remains a crucial bottleneck due to low yield handling in the device fabrication (e.g., disconnections between photo absorbent channels and readout electrodes). However, studies clarifying the above malfunction mechanism and associated dominant factors in device handling, such as specific fabrication or material selection steps, still need to be completed. To address this issue, this work introduces all-screen-coatable fabrication techniques for CNT film PTE imagers to enhance their physical and thermal durabilities. First, this work determined that the transfer of CNT films on supporting substrates dominantly governs the mechanical robustness of the channels and that thermal curing in the subsequent fabrication process is an essential factor in the yields of channel-electrode connections. The proposed approach ensures a transfer-free direct coating of the CNT film on diverse substrates and is sufficiently durable against thermal curing-induced disconnections at the channel-electrode interfaces. The screen-coating technique is also available for whole device materials of solution-processable CNT film PTE imagers, simplifying fabrication processes. All-screen-coatable CNT film PTE imagers synergize their inherent functional sensing and high-yield operations toward versatile applications. This study develops robust device design strategies of a multi-functional ultrabroadband freely deformable thin-film image sensor sheet with advantageous physical and thermal durabilities via highly versatile coating techniques. The device overcomes a long-standing fatal issue of ease of structural disconnections in designing such thin-film soft image sensor sheets and sheds light on a roadmap for the practical high-yield usage.image