Patent ID: 8876974

Claim:
A chemical vapor deposition apparatus comprising: a chamber having a gas inlet for introducing a processing gas into the chamber and a gas outlet for exhausting a gas out of the chamber; a susceptor having a surface capable of loading a substrate thereon positioned inside the chamber, wherein the processing gas is provided toward the surface of the susceptor; a shower head providing the processing gas toward the surface of the susceptor capable of loading a substrate thereon; an inert gas injection unit formed in a shape encircling the shower head and injecting an inert gas, and; a replaceable guide unit detachably installed inside the chamber to guide the gas in the chamber to the gas outlet, and the guide unit comprises: a first wall portion positioned in the chamber at a distance from a sidewall of the chamber and having first wall portion holes are formed at lower part of the first wall portion to create discharge path to the gas outlet, a curved portion extending from a lower end of the first wall portion toward the susceptor, a second wall portion surround the susceptor therein, and an extending portion extending from the first wall portion to the sidewall of the chamber and forming a path for discharging the gas to the gas outlet by connecting the extending portion to the first portion holes, and wherein the lower ends of the first and second wall portions of the guide unit are connected by the curved portion, and wherein the extending portion is formed above the curved portion, wherein the guide unit is arranged under the inert gas injection unit such that the upper end of the guide unit contacts with a lower surface of the inert gas injecting unit and the lower end of the guide unit contacts with an inner lower surface of the chamber, and therein the inert gas is provided along the front and rear surfaces of the upper end of the guide unit, wherein the flowing processing gas and inert gas are discharged out of the chamber through the gas outlet via the extending portion formed above the curved portion.