Under the condition of ultra-high vacuum, the vapor produced by heating with all kinds of required components, the molecular beam or atomic beam formed by hole collimation is sprayed directly on the single crystal substrate at the appropriate temperature, and the molecule or atom can "grow" layer by layer according to the crystal arrangement to form thin film on the substrate by controlling the molecular beam to scan the substrate.
The molecules (atoms) ejected from the source furnace reach the substrate surface in the form of "molecular beam" flow, and the growth rate can be strictly controlled by quartz crystal film thickness meter.
The growth rate of molecular beam epitaxial is slow, about 0.01 nm/s, which can realize monatomic (molecular) layer epitaxial with marked film thickness controllability.
The composition and magazine concentration of the film can be strictly controlled by adjusting the opening and closing of the baffle between the beam source and the substrate, and the selective epitaxial growth can also be realized.
Non-thermal equilibrium growth, the substrate temperature can be lower than the equilibrium temperature, achieve low temperature growth, can effectively reduce mutual diffusion and self-doping;
Combined with reflective high energy electron diffraction (RHEED) and other devices, in-situ observation and real-time monitoring can be realized.
Epitaxial growth of ultra-thin multi-layer two-dimensional structural materials and devices (supercharacter, quantum well, modulation-doped Heterojunction,quantum well laser, high electron mobility transistor, etc.); combined with other processes, one-dimensional and zero-dimensional nanomaterials (quantum wires,quantum dots, etc.) can be prepared.
