The invention relates to a method for preparing a large-area beta-phase In2Se3
single crystal film. The method comprises the following steps that: 1)
chemical cleaning and
chemical corrosion treatmentare carried out on a
silicon substrate with
crystal orientation of (111), so that a
hydrogen-passivated
silicon substrate with a clean surface can be obtained; 2) the prepared
silicon substrate is transferred into a
molecular beam epitaxy system, heating is performed to 180 DEG C, and degassing is performed until the vacuum degree of the
system is superior to 8*10 <-10 > mbar; (3) the substrate naturally cools to a growth temperature range after the substrate is degassed, and meanwhile, an In
beam source and a Se
beam source are opened to grow and synthesize an In2Se3 polycrystalline film; (4) the temperature of the substrate is immediately raised to 300-350 DEG C after the growth of the polycrystalline film is finished, and subsequent annealing is carried out for 5 minutes; and 5) heating is immediately stopped after annealing is finished, and the substrate naturally cools to
room temperature, so that a high-quality beta-phase In2Se3
single crystal film can be obtained. According tothe method for growing the beta-phase In2Se3 thin film, the
molecular beam epitaxy technology is combined with the subsequent in-situ annealing process, and the large-area high-quality beta-phase In2Se3
single crystal thin film can be prepared on the
hydrogen-passivated silicon substrate at a low temperature.