Transport Properties of Large-Area Transferred Bi2Se3 Films under Bending Strain

Bismuth selenide (Bi2Se3) is a well-studied topological insulator with topologically-protected surface states. However, little is known about how its transport properties change with strain. In this work, the electrical resistance of Bi2Se3 is investigated with respect to bending strain. Large area (10 mm x 10 mm) Bi2Se3 films are transferred to flexible substrates by two methods: an etchant-free approach employing polystyrene (PS), water, and thermal release tape (TRT), and a PMMA-assisted etchant-based technique. The etchant-free method successfully produced continuous films, but often introduces cracks, wrinkles, and pinholes, leading to increased electrical resistance and mechanical fragility under strain. Despite some material imperfections, these studies show how strain affects the transport properties of topological insulators.