Graphene-enabled laser lift-off for ultrathin displays

Laser lift-off (LLO) of ultrathin polyimide (PI) films is important in the manufacturing of ultrathin displays. However, conventional LLO technologies face challenges in separating the ultrathin PI films without causing mechanical and electrical damage to integrated devices. Here, we propose a graphene-enabled laser lift-off (GLLO) method to address the challenges. The GLLO method is developed by integrating chemical vapor deposition (CVD)-grown graphene at the interface between a transparent carrier and an ultrathin PI film, exhibiting improved processability and lift-off quality. In particular, the GLLO method significantly mitigates plastic deformation of the PI film and minimizes carbonaceous residues remaining on the carrier. The role of graphene is attributed to three factors: enhancement of interfacial UV absorption, lateral heat diffusion, and adhesion reduction, and experimentations and numerical simulations verify the mechanism. Finally, it is demonstrated that the GLLO method separates ultrathin organic light-emitting diode (OLED) devices without compromising performance. We believe that this work will pave the way for utilizing CVD graphene in various laser-based manufacturing applications.