Method for chemical vapor deposition capable of preventing contamination and enhancing film growth rate
View Patent ↗A method for chemical vapor deposition (CVD) comprises injecting a purge gas into a reaction chamber where substrates are located; and supplying a source material of vapor phase participating directly in forming a film on the substrates to an inside of the reaction chamber, thus forming a protective curtain in the inside of the reaction chamber by a mutual diffusion-suppressing action between the purge gas and source material.
1. A method for chemical vapor deposition (CVD) in a reaction chamber, a susceptor being located inside the reaction chamber, on which a substrate is placed and a film deposition is made as a result of chemical reactions with supplied source materials, the method comprising:
establishing a reactive gas confiner for surrounding the susceptor in the reaction chamber, the reactive gas confiner comprising a wall having a plurality of openings perforated for communication of inside with outside of the reactive gas confiner, wherein the wall of the reactive gas confiner is separated from the reaction chamber at a distance;
injecting a purge gas, which does not either dissolve or generate byproducts by itself, into an outside of the reactive gas confiner; and
supplying a source material of vapor phase participating directly in forming a film to an inside of the reactive gas confiner, a protective curtain between the source material and the purge gas being formed in the reactive gas confiner.
2. The method for CVD as recited in claim 1 , wherein the source material is a composition mixed with a main source material that participates directly in forming the film and an auxiliary source material for carrying, vaporizing or diluting the main source material.
3. The method for CVD as recited in claim 1 , wherein the source material is composed of only main source material of pure vapor without a carrier gas.
4. The method for CVD as recited in claim 1 , wherein the purge gas comprises at least one of Ar, N 2 , He, H 2 , O 2 gas, and a composition mixed with at least one of Ar, N 2 , He, H 2 , and O 2 .
5. The method for CVD as recited in claim 1 , wherein the reactive gas confiner has a plurality of openings through which the purge gas is introduced to the inside of the reactive gas confiner, thus preventing the source material from diffusing to the outside of the reactive gas confiner, and forming the protective curtain that prevents the source material from touching the reactive gas confiner.
6. The method for CVD as recited in claim 1 , wherein an amount of the purge gas injected to the outside of the reactive gas confiner is set much larger than that of the source material supplied to the inside of the reactive gas confiner to direct the protective curtain from the outside to the inside of the reactive gas confiner, thus preventing the source material from touching the reactive gas confiner.
7. The method for CVD as recited in claim 5 , wherein an amount of the purge gas injected to the outside of the reactive gas confiner is set much larger than that of the source material supplied to the inside of the reactive gas confiner to direct the protective curtain from the outside to the inside of the reactive gas confiner, thus preventing the source material from touching the reactive gas confiner.