Method for manufacturing semiconductor device and substrate processing apparatus
A method for manufacturing a semiconductor device is provided. In the method, a silicon-containing gas is supplied to a substrate having a recess in a surface thereof at a predetermined film deposition temperature, thereby depositing a first silicon film in the recess. Chlorine and hydrogen are supplied to the substrate while maintaining the predetermined film deposition temperature, thereby etching the first silicon film deposited in the recess to expand an opening width of the first silicon film. The silicon-containing gas is supplied to the substrate while maintaining the predetermined film deposition temperature, thereby further depositing a second silicon film on the first silicon film in the recess.
1. A method for manufacturing a semiconductor device, the method comprising:
supplying a silicon-containing gas to a substrate having a recess in a surface thereof at a predetermined film deposition temperature, thereby depositing a first silicon film in the recess;
simultaneously supplying only both Cl 2 gas and H 2 gas to the substrate while maintaining the predetermined film deposition temperature, thereby etching the first silicon film deposited in the recess to expand an opening width of the first silicon film, a ratio of a flow rate of the H 2 gas to a flow rate of the Cl 2 gas being 1/10 or above; and
supplying the silicon-containing gas to the substrate while maintaining the predetermined film deposition temperature, thereby further depositing a second silicon film on the first silicon film in the recess.
2. The method as claimed in claim 1 ,
wherein the simultaneously supplying only both Cl 2 gas and H 2 gas to the substrate and the supplying the silicon-containing gas to the substrate while maintaining the predetermined film deposition temperature are alternately repeated.
3. The method as claimed in claim 2 , wherein the simultaneously supplying only both Cl 2 gas and H 2 gas to the substrate and the supplying the silicon-containing gas to the substrate while maintaining the predetermined film deposition temperature are repeated until the recess is filled with the first and second silicon films.
4. The method as claimed in claim 3 ,
wherein the substrate has a plurality of recesses having different aspect ratios in the surface, and
wherein the plurality of recesses is sequentially filled with the first and second silicon films in descending order of aspect ratio.
5. The method as claimed in claim 1 , wherein the predetermined film deposition temperature is in a range of 440 degrees C. to 530 degrees C. inclusive.
6. The method as claimed in claim 1 , wherein the silicon-containing gas is SiH 4 gas.
7. The method as claimed in claim 1 , wherein the simultaneously supplying only both Cl 2 gas and H 2 gas to the substrate comprises supplying Cl 2 gas while adding H 2 gas to the Cl 2 gas.
8. The method as claimed in claim 1 , wherein the flow rate of the Cl 2 gas being 300 sccm, and the flow rate of the H 2 gas being in a range of 30 sccm to 1000 sccm.