High‐Modulus Skeleton‐Reinforced PDMS Microstamps for Precision Transfer Printing of Microscale Devices

ABSTRACT Deterministic assembly of microscale devices enables heterogeneous integration in advanced electronic, optoelectronic, and display systems. These applications require precise placement of components such as micro‐light‐emitting diodes (micro‐LEDs), thin‐film transistors, and sensors onto rigid or flexible receiving substrates. Transfer printing provides a scalable route for this alignment‐sensitive assembly, but lateral and rotational misalignment during manufacturing remain important limitations. Conventional elastomeric stamps based on poly(dimethylsiloxane) (PDMS) deform under contact loading, particularly in micropillar configurations, where pillar bending produces positional error and reduces transfer fidelity. Here, we introduce a skeleton‐reinforced hybrid PDMS micropillar stamp that suppresses deformation while retaining the compliant interface required for reliable pick‐up and release. Each pillar contains an embedded high‐modulus PDMS skeleton surrounded by soft PDMS at the periphery and contact surface. The internal skeleton constrains pillar deformation, while the compliant outer layer preserves conformal contact and interfacial adhesion. This architecture improves dimensional stability during compression and reduces sliding of supported microscale devices on receiving substrates. The hybrid stamp therefore provides a scalable strategy for precision transfer printing in high‐resolution displays, flexible electronic systems, and heterogeneous microsystems.