Mechanics of magnet-controlled transfer printing

A recently developed magnet-controlled dry adhesive, which offers rapidly tunable and highly reversible adhesion in both air and vacuum, is valuable to develop the magnet-controlled transfer printing for heterogeneous materials integration. An analytical mechanics model based on the energy method is developed to identify the underlying mechanism of the magnet-controlled transfer printing and to predict the interfacial delamination between the magnet-controlled stamp and the ink in the applied magnetic field. The analytical predictions agree well with experiments. The influences of the magnetic pressure, material properties, and geometric parameters of the stamp on the adhesion strength are fully investigated. The critical condition for non-contact printing, validated by experiments, is obtained to eliminate the constraints from the receiver substrate. These results may serve as the theoretical basis for stamp optimization, especially for determining optimal condition for the magnet-controlled transfer printing.