Heating-mode-defined energy pathways govern non-contact release in shape memory polymer transfer printing
Shape memory polymer (SMP)-based transfer printing offers a promising route for heterogeneous integration of flexible electronics, yet non-contact release reliability remains a critical bottleneck. This study systematically investigates the influence of pickup heating modes—localized versus global—on the release yield and energy-delivery mechanisms through combined experiments and finite element simulations. The localized heating mode concentrates strain energy at the interface, enabling controlled chip ejection with high yield, whereas global heating dissipates energy, leading to release failure. Quantitative analysis reveals that localized heating achieves a release yield of 100% under optimized conditions, compared to near-zero for global heating. The ejection velocity under localized heating is higher, which may induce chip bouncing on the receiver substrate, affecting transfer accuracy; however, this can be mitigated by adjusting release gap and laser parameters. The findings establish a theoretical framework for energy pathway design, providing guidelines for achieving high-yield, accurate non-contact release in laser-induced transfer printing. This work advances the practical application of SMP-based transfer printing for micro-LED displays and flexible electronics, addressing a key manufacturing bottleneck.