基于激光辅助转移印刷的Micro-LED巨量转移

Micro-LED显示技术由于具有高亮度、自发光等优势而成为显示领域的热点，被视为下一代新型显示技术。巨量转移是指将大量Micro-LED芯片从生长基板转移到另一个基板或载体上的技术过程，是实现Micro-LED全彩化显示的重要方法之一。然而，巨量转移面临着诸多挑战：首先，Micro-LED具有尺寸小、数量多的特点，在转移过程中容易发生位移和损伤；其次，要实现显示屏的集成，需要转移数百万个Micro-LED器件，因此对于巨量转移的良率和速率都提出了极高的要求。

针对如何实现高良率高速率的巨量转移技术，本文开展了以下研究：根据巨量转移的需求，设计并制备了器件间相互独立的倒装结构蓝光Micro-LED阵列，对从外延片清洗到金属焊盘蒸镀的半导体加工工艺做出了详细的介绍。接着设计了倒装结构Micro-LED阵列的巨量转移方法，将激光剥离技术用于剥离蓝宝石衬底，利用柔性薄膜的粘性差异对Micro-LED阵列进行两度翻转，单次转移阵列面积6.5×8 mm²，转移器件数量达到2万以上，转移良率可以达到99.35%，实现了高速率高良率的巨量转移过程。通过对转移前后的Micro-LED阵列进行电学光学测试对比，证实了所设计的巨量转移过程没有对Micro-LED器件有源区造成损伤，并且Micro-LED器件的半峰全宽由于激光剥离过程中的高温影响而得到了改善。

综合来说，本文的研究成果为克服Micro-LED巨量转移技术面临的挑战提供了技术方案和实验验证，为其在显示技术领域的进一步应用提供了可靠的基础和支持。

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