Growth of Bi₂Se₃ topological insulator films using a selenium cracker source

In this article, the authors describe growth of high-quality Bi₂Se₃ topological insulator films using a selenium cracking source on c-plane sapphire substrates. Films are grown using molecular beam epitaxy and characterized by Hall effect measurements and atomic force microscopy. The use of a cracker sources results in films with low carrier density and reduced aging effects. Growth conditions giving the best electrical properties correspond with the best surface structure as determined by atomic force microscopy. This improved film quality opens the door to the creation of real electronic or spintronic devices based on these unique materials.