Patent ID: 6277201
Filing Date: 2001-08-21
Classification: C23C

Abstract:
A CVD apparatus for forming a thin film on a surface of a semiconductor substrate under reduced pressure, comprising:(a) a reaction chamber;(b) a vacuum device connected to the reaction chamber for vacuuming and exhausting the reaction chamber;(c) a susceptor that maintains the semiconductor substrate inside the reaction chamber;(d) a showerhead that supplies a reaction gas to the surface of the semiconductor substrate set on the susceptor; and(e) a liquid-source vaporization system connected to the showerhead, which is disposed upstream of the showerhead and is used for atomizing and vaporizing the liquid reaction material at a given flow rate prior to its entry into the reaction chamber, said liquid-source vaporization system comprising:(i) a horn-type atomizer connected to a liquid reaction material supply source, said atomizer atomizing the liquid reaction material from the supply source by ultrasonic vibration, said atomizer having a tip from which the atomized reaction material is discharged;(ii) a carrier gas supplier disposed to surround the horn-type atomizer upstream of the tip of the atomizer to spout a carrier gas which is mixed with the atomized reaction material; and(iii) a hollow casing constituting a vaporizer connected to the atomizer to vaporize the atomized reaction material in the hollow casing, said hollow casing being equipped with a heater, wherein the tip of the horn-type atomizer and the carrier gas supplier are arranged inside the hollow casing.