Film Forming Method Using Epitaxial Growth and Epitaxial Growth Apparatus

Abstract

When a reaction chamber defined and formed by a ceiling plate as a top face, a substrate mounting portion as a bottom face, and a side wall as a lateral face is constructed, the ceiling plate is supported by a support at the circumferential edge of the ceiling plate from the upper side and the outer side of the circumferential edge, and the reactant gas is rectified in a reactant gas supply path disposed in the side wall so that a horizontal component in a flow direction of the reactant gas in the reaction chamber corresponds to a horizontal component in a direction extending from the center of an opening of the reactant gas supply path facing the reaction chamber to the center of the reaction chamber.

What is claimed is: 
     
         1 . A film forming method using epitaxial growth that is performed in a reaction chamber of which the top face, the bottom face, and the lateral face are defined and formed by a ceiling plate, a substrate mounting portion having a substrate horizontally mounted thereon, and a side wall, the ceiling plate being supported at the circumferential edge of the ceiling plate from the upper side and the outer side of the circumferential edge, the film forming method comprising:
 heating the reaction chamber to a predetermined growth temperature;   rectifying the reactant gas in a reactant gas supply path disposed in the side wall so that a horizontal component in a flow direction of the reactant gas in the reaction chamber corresponds to a horizontal component in a direction extending from the center of an opening of the reactant gas supply path facing the reaction chamber to the center of the reaction chamber;   introducing the rectified reactant gas into the reaction chamber in the horizontal direction from the reactant gas supply path;   forming a film on the top surface of the substrate using the reactant gas while causing the substrate to rotate about an axis in the vertical direction passing through the center of the substrate mounting portion; and   discharging the reactant gas used to form the film to a gas discharge path disposed at a position of the side wall opposed to the reactant gas supply path with the center of the reaction chamber interposed therebetween.   
     
     
         2 . The film forming method according to  claim 1 , wherein the ceiling plate is supported so that a distance between the ceiling plate and the top surface of the substrate is equal to or less than a predetermined value. 
     
     
         3 . The film forming method according to  claim 1 , wherein the reactant gas supply path is formed in a step shape ascending from an entrance of the reactant gas to an exit connected to the reaction chamber, and
 wherein the rectifying of the reactant gas includes mixing a plurality of source gases which are raw materials of the reactant gas in the reactant gas supply path of the step shape.   
     
     
         4 . The film forming method according to  claim 1 , wherein the gas discharge path is connected to a gas discharge portion disposed outside the side wall and the gas discharge portion is formed to have an opening narrowing from the inside connected to the gas discharge path to the outside, and
 wherein the film forming method further comprises discharging the reactant gas to the outside through the gas discharge path.   
     
     
         5 . The film forming method according to  claim 1 , wherein the heating of the reaction chamber includes pre-heating the reactant gas by the use of a susceptor ring disposed on the outer circumference of the substrate mounting portion,
 wherein the susceptor ring includes an outer ring portion mounted on a flange portion disposed in the side wall and an inner ring portion mounted on a concave portion disposed on the top surface of the outer ring portion, and the inner ring portion has such an inner diameter to reduce a gap between the circumferential edge of the substrate mounting portion and the inner circumferential edge of the outer ring portion, and   wherein the film forming method further comprises preventing the reactant gas from flowing from the circumferential edge of the substrate mounting portion to the bottom surface of the substrate mounting portion by the use of the inner ring portion.   
     
     
         6 . An epitaxial growth apparatus that forms a film on the top surface of a substrate in a reaction chamber using epitaxial growth, comprising:
 a reaction chamber of which the top face, the bottom face, and the lateral face are defined and formed by a ceiling plate, a substrate mounting portion having a substrate horizontally mounted thereon and rotating about an axis in the vertical direction passing through the center of the substrate, and a side wall;   a reactant gas supply path that is formed in the side wall so as to supply a reactant gas to the reaction chamber;   a gas discharge path that is formed at a position of the side wall facing the reactant gas supply path with the center of the reaction chamber interposed therebetween so as to discharge the reactant gas passing through the reaction chamber to the outside;   a support that supports the ceiling plate at the circumferential edge of the ceiling plate from the upper side and the outer side of the circumferential edge; and   rectification means for rectifying the reactant gas in the reactant gas supply path so that a horizontal component in a flow direction of the reactant gas in the reaction chamber corresponds to a horizontal component in a direction extending from the center of an opening of the reactant gas supply path facing the reaction chamber to the center of the reaction chamber.   
     
     
         7 . The epitaxial growth apparatus according to  claim 6 , wherein the substrate mounting portion has a plurality of through-holes. 
     
     
         8 . The epitaxial growth apparatus according to  claim 6 , wherein the gas discharge path is connected to a gas discharge portion disposed outside the side wall and the gas discharge portion is formed to have an opening narrowing from the inside connected to the gas discharge path to the outside. 
     
     
         9 . The epitaxial growth apparatus according to  claim 6 , further comprising:
 first heating means that is disposed above the reaction chamber so as to heat the reaction chamber to a predetermined growth temperature;   a first reflector that is disposed above the first heating means;   second heating means that is disposed below the reaction chamber so as to heat the reaction chamber to a predetermined growth temperature; and   a second reflector disposed to below the second heating means,   wherein the first reflector includes a first slope portion reflecting heat waves from the first heating means to the center of the reaction chamber and a first flat portion reflecting heat waves from the first heating means in a vertically-falling direction, and the first slope portion and the first flat portion are arranged so that an area ratio of the first slope portion and the first flat portion is a predetermined ratio and a distribution of the first slope portion and the first flat portion is not biased, and   wherein the second reflector includes a second slope portion reflecting heat waves from the second heating means to the center of the reaction chamber and a second flat portion reflecting heat waves from the second heating means in a vertically-rising direction, and the second slope portion and the second flat portion are arranged so that an area ratio of the second slope portion and the second flat portion is a predetermined ratio and a distribution of the second slope portion and the second flat portion is not biased.