Laser Shock-Induced Conformal Transferring of Functional Devices on 3-D Stretchable Substrates

This paper discussed a top-down integration method to achieve the three-dimensional (3-D) microscale conformal transferring of functional devices on flexible elastomeric substrates at ambient conditions. By the tunable laser-induced pressure, the functional device inherits the microscale wrinkle-like patterns, without compromising functions. The functional materials are encapsulated in the biocompatible parylene layers to avoid the drastic plastic deformations in functional layers. The electrical resistivity of functional device increases marginally with the applied laser intensity, aspect ratios of microscale features, and overall tensile strain applied to the whole flexible assembly. The stretchability of the transferred functional devices was studied by measuring the electrical property as function of bending and tensile strains. It shows that the device can sustain more than 40% strain in the stretchable substrate. It is demonstrated that the process can achieve the flexible and stretchable functional integration conformal to 3-D micrometer-patterns in a fast and scalable way.