Fig. 1
From: Biointerfaces with ultrathin patterns for directional control of cell migration
Fabrication technology and micrographs of patterned titanium oxide (TiOx) on polydimethylsiloxane (PDMS) substrate. (a) Spin-coating of polyvinyl alcohol (PVA) film onto PDMS substrate, followed by drying on hotplate. (b) Spin-coating of photoresist onto PVA film. (c) Transfer of patterns onto PVA surface using UV lithography. (d) Reactive ion etching (RIE) PVA film to form undercut profile. (e) Deposition of thin layer of TiOx on PDMS using electron beam evaporation. (f) Formation of patterned TiOx on PDMS substrate by liftoff. Micrographs of patterned TiOx in arrowhead shape are shown, with arrowhead arms of lengths of (g) 10, (h) 20, (i) 35, and (j) 60 μm. The arrowhead arms were 5 μm wide with 5 μm separation, and arrowhead tip angle was 45°