In some aspects, methods of forming a metal selenide or metal telluride thin film are provided. According to some methods, a metal selenide or metal telluride thin film is deposited on a substrate in a reaction space in a cyclical deposition process where at least one cycle includes alternately and sequentially contacting the substrate with a first vapor-phase metal reactant and a second vapor-phase selenium or tellurium reactant. In some aspects, methods of forming three-dimensional architectures on a substrate surface are provided. In some embodiments, the method includes forming a metal selenide or metal telluride interface layer between a substrate and a dielectric. In some embodiments, the method includes forming a metal selenide or metal telluride dielectric layer between a substrate and a conductive layer.