Molecular beam epitaxy

Molecular beam epitaxy grows crystalline films by directing controlled beams of material toward a crystalline substrate in a vacuum system. A typical apparatus has source cells, shutters, a heated substrate holder and diagnostic tools such as electron diffraction. Opening or closing shutters changes which species reach the surface, enabling layered heterostructures. Growth quality depends on surface diffusion, incorporation and desorption as well as the arriving flux. The method's value is precise control of composition and interfaces; depositing material in vacuum alone does not ensure epitaxial crystal ordering.