Fig. 3: Design of buckling configuration and the related fabrication mechanism.
From: Nanoscale three-dimensional fabrication based on mechanically guided assembly
a Definition of the design parameters of the substrate. b Determinants by substrate microstructure for controlling the three components of buckling configuration (i.e., direction, deflection, and mode). c Mechanism of buckling direction control. c-i Schematic effect of pillar strain on buckling direction. c-ii Confocal laser scanning microscopy images and finite element method simulation results showing the effects of pillar strain on the pillar edge shape. c-iii Number of convex shapes (upward buckling) depending on pillar strain. d Mechanism of buckling deflection control. d-i Schematic dependence of buckling deflection on trench strain. d-ii Effects of trench strain on the maximal z-directional deflection of the buckled beam determined using experiments, theoretical analysis, and finite element method simulation. d-iii Experimental and simulated results of overall beam configurations under the applied printing conditions (applied external strain (εsubstrate) = 5%). e Mechanism of buckling mode control. e-i Schematic of the dependence of buckling mode on the boundary constraints. e-ii Confocal laser scanning microscopy and scanning electron microscopy images of the buckled beam acquired for different boundary constraints with various pillar widths. e-iii Experimental and simulation results obtained for buckled beams with the designed modes printed using different pillar sizes and arrangements.
