Laser processing of transition metal oxide thin-film transistors for large-area flexible OLED displays

大面积电子制造的传统方法依赖于直接单片集成。虽然针对刚性高熔点基板（例如硅或玻璃）进行了优化，但这些工艺可能不是制造柔性电子器件的最佳方法。在许多情况下，从热提取、机械性能、热机械行为、光学透明度、导电性或化学相容性的观点来看，用于特定薄膜异质结构的理想生长衬底可能不是理想衬底。在这些情况下，去除生长基质可能更有利，尽管如果该方法仅涉及机械或化学手段则并不总是实用的。在透明衬底上使用吸收薄膜的激光加工已被证明在加工用于超高输出发光二极管的宽带隙器件中是有效的。脉冲激光加工提供了加热受控体积材料的空间能力，该受控体积材料由照射区域和固体的热扩散长度限定。这种空间控制允许薄膜结构的选择性分解，而不影响加热区外部的周围材料。选择性剥离工艺与晶片键合工艺相结合，将使透明衬底上的薄膜晶体管能够从原始生长衬底上移除，并集成到优化的平台上，以增强性能和功能。

Conventional approaches to large-area electronics fabrication relies on direct monolithic integration. While optimized for rigid high-melting point substrates, such as silicon or glass, these processes may not be the best approach for fabricating flexible electronics. In many cases, the ideal growth substrate for a specific thin-film heterostructure may not be the ideal substrate from the standpoint of heat extraction, mechanical properties, thermomechanical behavior, optical transparency, electrical conductivity or chemical compatibility. In these situations, it may be more advantageous to remove the growth substrate, although it is not always practical if the approach involves only mechanical or chemical means. Laser processing using absorbing thin films on transparent substrates has been shown to be effective in processing wide-bandgap devices for ultra-high output light-emitting diodes. Pulsed-laser processing provides the spatial capability of heating a controlled volume of material defined by the irradiation area and the thermal diffusion length of the solid. This spatial control allows for selective decomposition of thin-film structures that does not affect the surrounding material outside the heating zone. A selective liftoff process combined with wafer bonding processes will enable thin-film transistors on transparent substrates to be removed from the original growth substrate and integrated onto optimized platforms to enhance performance and functionality.