Large-area, programmable assembly of diverse micro-objects onto arbitrary substrates is a fundamental yet challenging task. Herein a simple wafer-level micro-assembly technique based on the light-triggered change in both surface topography and interfacial adhesion of a soft photo-sensitive polymer is proposed. In particular, the light-regulated polymer growth creates locally indented and elevated zones on the stamp surface. The light-mediated adhesion reduction, on the other hand, facilitates the inks to be released from the polymer. The interplay of these two effects makes it feasible for the programmable assembly of ultra-small components onto various substrates coated with supplementary adhesive layers. The fidelity of this technique is validated by assembling diverse materials and functional devices, with the printing size up to 4-inch. This work provides a rational strategy for large-scale and programmable assembly of diverse delicate micro-objects, bypassing the common issues of some existing techniques such as poor transfer uniformity, small printing area, and high cost.

将各种微型物体大面积、可编程地组装到任意基板上是一项基本但具有挑战性的任务。本文提出了一种简单的晶圆级微组装技术，该技术基于软光敏聚合物的表面形貌和界面粘附的光触发变化。特别是，光调节聚合物的生长在印模表面上产生了局部凹陷和升高的区域。另一方面，光介导的附着力降低有助于油墨从聚合物中释放出来。这两种效应的相互作用使得将超小型元件可编程组装到涂有补充粘合剂层的各种基板上成为可能。这项技术的保真度通过组装不同的材料和功能设备得到验证，打印尺寸高达 4 英寸。