Figure 4.

Fabrication and characterization of microwell arrays. a) Illustration of the fabrication of microwell arrays. b) Photoimages of STL printed micropillar arrays with 800 × 800 µm pillar size (scale bar, 2.5 mm), SMP sample (scale bar, 5 mm), and 4D microwell arrays with 800 × 800 µm well size (scale bar, 5 mm). c) Shape transformation process from microwell to flat with the sample having an 800 × 800 µm well size. When incubated in water bath at 37 °C, the microwell arrays were gradually transformed, which were still visible at three days, and almost restored its original flat surface after seven days. d) Dynamic recovery process of the strip sample and microwell array sample demonstrated by the relationship between recovery degree and incubation time.