Method for manufacturing silicon epitaxial wafer and method for manufacturing semiconductor device
A method for manufacturing a silicon epitaxial wafer includes: preparing a test silicon wafer in advance, forming the multilayer film on a surface of the test silicon wafer, and measuring a warp direction and a warp amount (Warp) W of the silicon wafer having the multilayer film formed thereon; and selecting a silicon wafer as a device formation substrate and conditions for forming an epitaxial layer which is formed on the silicon wafer as the device formation substrate in such a manner that a warp which cancels out the measured warp amount W is formed in a direction opposite to the measured warp direction, and forming the epitaxial layer on a surface of the selected silicon wafer as the device formation substrate where the multilayer film is formed under the selected conditions for forming the epitaxial layer.
1. A method for manufacturing a silicon epitaxial wafer which is constituted of a silicon wafer and an epitaxial layer formed on the silicon wafer, the silicon epitaxial wafer being configured to form a multilayer film on the epitaxial layer comprising:
preparing a test silicon wafer in advance, forming the multilayer film on a surface of the test silicon wafer, and measuring a warp direction and a warp amount W of the test silicon wafer having the multilayer film formed thereon; and
selecting a silicon wafer as a device formation substrate and conditions for forming an epitaxial layer which is formed on the silicon wafer as the device formation substrate in such a manner that a warp which cancels out the measured warp amount W is formed in a direction opposite to the measured warp direction, and forming the epitaxial layer on a surface of the selected silicon wafer as the device formation substrate where the multilayer film is formed under the selected conditions for forming the epitaxial layer.
2. The method for manufacturing a silicon epitaxial wafer according to claim 1 ,
wherein, at the step of forming the epitaxial layer, a silicon wafer having germanium or tin doped therein is used as the silicon wafer which is the device formation substrate in case of forming a concave warp which recesses the epitaxial layer side to the silicon epitaxial wafer, and a silicon wafer having phosphorus or boron doped therein is used as the silicon wafer which is the device formation substrate in case of forming a convex warp which protrudes the epitaxial layer side to the silicon epitaxial wafer.
3. The method for manufacturing a silicon epitaxial wafer according to claim 2 ,
wherein, at the step of forming the epitaxial layer, conditions for the silicon wafer as the device formation substrate and the conditions for forming the epitaxial layer are determined by the following expression in such a manner that a warp amount of a warp formed to the silicon epitaxial wafer becomes the warp amount W, wherein, W is a positive value in case of forming a concave shape which recesses a multilayer film side to the silicon wafer having the multilayer film formed thereon, and W is a negative value in case of forming a convex warp which protrudes the multilayer film side to the silicon wafer having the multilayer film formed thereon:
W ={(3× l 2 ×h f )/(4× h S 2 )}×{( r Si −r X )/ r Si }×[ X ]/ N S
where l: a diameter of the silicon wafer as the device formation substrate,
h f : a thickness of the epitaxial layer,
h s : a thickness of the silicon wafer as the device formation substrate,
r Si : a covalent radius of Si,
r X : a covalent radius of an element which is doped in the silicon wafer as the device formation substrate,
N S : atomic density of Si, and
[X]: dope concentration of the element which is doped in the silicon wafer as the device formation substrate.
4. The method for manufacturing a silicon epitaxial wafer according to claim 3 ,
wherein the multilayer film is a multilayer film provided by alternately laminating an SiO 2 film and an SiN film or a multilayer film provided by alternately laminating the SiO 2 film and a polysilicon film.
5. A method for manufacturing a semiconductor device, the method comprising forming the multilayer film on a surface of a silicon epitaxial wafer, which is manufactured by the method for manufacturing a silicon epitaxial wafer according to claim 4 , where the epitaxial layer has been formed.
6. A method for manufacturing a semiconductor device, the method comprising forming the multilayer film on a surface of a silicon epitaxial wafer, which is manufactured by the method for manufacturing a silicon epitaxial wafer according to claim 3 , where the epitaxial layer has been formed.
7. The method for manufacturing a silicon epitaxial wafer according to claim 2 ,
wherein the multilayer film is a multilayer film provided by alternately laminating an SiO 2 film and an SiN film or a multilayer film provided by alternately laminating the SiO 2 film and a polysilicon film.
8. A method for manufacturing a semiconductor device, the method comprising forming the multilayer film on a surface of a silicon epitaxial wafer, which is manufactured by the method for manufacturing a silicon epitaxial wafer according to claim 7 , where the epitaxial layer has been formed.
9. A method for manufacturing a semiconductor device, the method comprising forming the multilayer film on a surface of a silicon epitaxial wafer, which is manufactured by the method for manufacturing a silicon epitaxial wafer according to claim 2 , where the epitaxial layer has been formed.
10. The method for manufacturing a silicon epitaxial wafer according to claim 1 ,
wherein, at the step of forming the epitaxial layer, conditions for the silicon wafer as the device formation substrate and the conditions for forming the epitaxial layer are determined by the following expression in such a manner that a warp amount of warp formed to the silicon epitaxial wafer becomes the warp amount W, wherein, W is a positive value in case of forming a concave shape which recesses a multilayer film side to the silicon wafer having the multilayer film formed thereon, and W is a negative value in case of forming a convex warp which protrudes the multilayer film side to the silicon wafer having the multilayer film formed thereon;
W ={(3× l 2 ×h f )/(4× h S 2 )}×{( r Si −r X )/ r Si }×[ X ]/ N S
where l: a diameter of the silicon wafer as the device formation substrate,
h f : a thickness of the epitaxial layer,
h S : a thickness of the silicon wafer as the device formation substrate,
r Si : a covalent radius of Si,
r X : a covalent radius of an element which is doped in the silicon wafer as the device formation substrate,
N S : atomic density of Si, and
[X]: dope concentration of the element which is doped in the silicon wafer as the device formation substrate.
11. The method for manufacturing a silicon epitaxial wafer according to claim 10 ,
wherein the multilayer film is a multilayer film provided by alternately laminating an SiO 2 film and an SiN film or a multilayer film provided by alternately laminating the SiO 2 film and a polysilicon film.
12. A method for manufacturing a semiconductor device, the method comprising forming the multilayer film on a surface of a silicon epitaxial wafer, which is manufactured by the method for manufacturing a silicon epitaxial wafer according to claim 11 , where the epitaxial layer has been formed.
13. A method for manufacturing a semiconductor device, the method comprising forming the multilayer film on a surface of a silicon epitaxial wafer, which is manufactured by the method for manufacturing a silicon epitaxial wafer according to claim 10 , where the epitaxial layer has been formed.
14. The method for manufacturing a silicon epitaxial wafer according to claim 1 ,
wherein the multilayer film is a multilayer film provided by alternately laminating an SiO 2 film and an SiN film or a multilayer film provided by alternately laminating the SiO 2 film and a polysilicon film.
15. A method for manufacturing a semiconductor device, the method comprising forming the multilayer film on a surface of a silicon epitaxial wafer, which is manufactured by the method for manufacturing a silicon epitaxial wafer according to claim 14 , where the epitaxial layer has been formed.
16. A method for manufacturing a semiconductor device, the method comprising forming the multilayer film on a surface of a silicon epitaxial wafer, which is manufactured by the method for manufacturing a silicon epitaxial wafer according to claim 1 , where the epitaxial layer has been formed.