The invention discloses a
quantum dot device and a preparation method thereof.The
quantum dot device comprises a substrate, a
semiconductor layer, a barrier regulation and control part and a control
electrode, the
semiconductor layer is formed on one side of the substrate and comprises a source region, a drain region and a channel region located between the source region and the drain region, and the channel region comprises a channel body and a containing space; the channel body comprises at least one
quantum dot region, and two sides of the
quantum dot region are respectively provided with an accommodating space; the potential barrier regulation and control part is located in the accommodating space, and the potential barrier regulation and control part is used for regulating the tunneling potential barrier of the channel region; the control electrodes are located on the sides, away from the substrate, of the
quantum dot areas and correspond to the
quantum dot areas one to one. According to the quantum dot device provided by the invention, the potential barrier adjusting part is arranged in the
semiconductor layer, so that the tunneling potential barrier in the channel region can be adjusted and controlled, the tunneling potential barrier can be increased or decreased, and the quantum dot device with ideal working current is obtained.