Method and apparatus for feeding a gas for epitaxial growth

An apparatus for feeding a gas for epitaxial growth, comprising:

• a vaporizer for heating a liquid raw material to vaporize the liquid raw material by water having a temperature of the liquid raw material's boiling point or higher,
• a first mass flow controller for controlling a vaporized ingredient gas at the vaporizer to have a first predetermined mass flow,
• a second mass flow controller for controlling a carrier gas to have a second predetermined mass flow,
• a mixer for mixing the ingredient gas and the carrier gas controlled into the respective first and second predetermined mass flows,
• a first flow adjusting valve for adjusting the flowing amount of the mixed gas composed of the ingredient gas and the carrier gas,
• a tube for feeding the flow-adjusted mixed gas into a reactor for epitaxial growth,
• a means for heating the ingredient gas and the mixed gas to over the respective condensing points for the ingredient gas and the mixed gas and maintaining the ingredient gas and the mixed gas at a temperature above the respective condensing points between the ingredient gas feeding tube of the vaporizer and the flow-adjusted mixed gas feeding tube for the reactor,
• a pressure sensor for measuring a pressure of the ingredient gas inside the vaporizer,
• a second flow adjusting valve for adjusting the feeding amount of the liquid raw material into the vaporizer, and
• a controller for controlling the second flow adjusting valve on the basis of pressure measured by the pressure sensor.