Device and method for mist chemical vapor deposition of large-size semiconductor thin film

A device for mist chemical vapor deposition of a large-size semiconductor thin film, comprising an atomization unit, a reactor, a buffer showerhead, and a rotary base, wherein

• the buffer showerhead is arranged inside the reactor, and the buffer showerhead comprises a conveying pipe, a conical transition segment and a cylindrical segment connected in sequence from left to right;
• the conveying pipe passes through one end of the reactor and is connected to the atomization unit, and the atomization unit is further provided with a carrier gas input port;
• a first buffer plate and a second buffer plate are arranged in the cylindrical segment in sequence from left to right, and the first buffer plate and the second buffer plate divide the cylindrical segment into three portions, and the three portions are a first buffer area, a second buffer area and a growing area;
• the first buffer plate is of a conical plate structure, an apex of the conical plate structure is away from the second buffer plate, and the first buffer plate is provided with a plurality of straight holes perpendicular to the second buffer plate, and the second buffer plate is provided with a plurality of inclined holes;
• the rotary base directly opposite to the second buffer plate is arranged at the growing area, and a substrate is fixed onto the rotary base and is surrounded by a cylindrical segment of the growing area;
• the rotary base is driven to rotate by a first motor arranged outside the reactor, the first motor is mounted on a mobile unit, and the mobile unit drives the first motor and the rotary base to move toward a direction close to or away from the second buffer plate;
• wherein each of the straight holes has a diameter of 2 mm-10 mm, a distance between every two adjacent straight holes is 2 mm-5 mm, and the inclined hole has a diameter of 2 mm-10 mm;
• the diameter of the straight hole is equal to the diameter of the inclined hole;
• the inclined holes and the straight holes are equal in number and in a one-to-one correspondence;
• and
• an included angle between a central axis of the inclined hole and a surface normal of the second buffer plate is 30°-70°.