The invention discloses a
silicon nitride thin film deposition method and vertical LPCVD equipment. The method comprises the steps that S1, the standby temperature of a process cavity is set; s2, the
wafer boat rises to a process position at a
constant speed, and
nitrogen is introduced between the inner
pipe and the outer
pipe; s3, closing the
nitrogen, and vacuumizing the cavity; s4, introducing
nitrogen into the cavity, and keeping the pressure in the cavity at P3; s5, evacuating the nitrogen in the cavity, and introducing
ammonia gas; s6, under the condition that only
ammonia gas flows, the pressure in the cavity is kept at P4; s7, introducing
dichlorosilane into the cavity, and carrying out
silicon nitride film deposition; s8, closing the
dichlorosilane, keeping the
ammonia gas flow unchanged, and consuming residual
dichlorosilane; s9, removing
ammonia gas; and S10, the process cavity recovers to normal pressure, the
wafer boat descends at a
constant speed, and nitrogen is introduced between the inner
pipe and the outer pipe. The method has the characteristics of simple principle, high film forming stability, low
pollution degree and the like, and overcomes the defect that the surface of the existing
silicon nitride film is easily polluted by particles.