Method of manufacturing semiconductor device
A method of manufacturing a semiconductor device capable of realizing a high yield of a large-scale semiconductor device even when a silicon carbide semiconductor including a defect is used is provided. The method of manufacturing a semiconductor device includes: a step of epitaxially growing a silicon carbide semiconductor layer on a silicon carbide semiconductor substrate; a step of polishing a surface of the silicon carbide semiconductor layer; a step of ion-implanting impurities into the silicon carbide semiconductor layer after the step of polishing; a step of performing heat treatment to activate the impurities; a step of forming a first thermal oxide film on the surface of the silicon carbide semiconductor layer after the step of performing heat treatment; a step of chemically removing the first thermal oxide film; and a step of forming an electrode layer on the silicon carbide semiconductor film.
1. A method of manufacturing a semiconductor device, comprising:
growing epitaxially a silicon carbide semiconductor layer on a silicon carbide semiconductor substrate;
polishing a surface of the silicon carbide semiconductor layer;
ion-implanting impurities into the silicon carbide semiconductor layer after the polishing;
performing a heat treatment to activate the impurities;
forming a first thermal oxide film on the surface of the silicon carbide semiconductor layer after the performing the heat treatment;
removing chemically the first thermal oxide film; and
forming an electrode layer on the silicon carbide semiconductor film.
2. The method according to claim 1 , wherein the polishing is performed by chemical mechanical polishing (CMP).
3. The method according to claim 2 , wherein an amount of polishing of the silicon carbide semiconductor layer is 4 μm or more.
4. The method according to claim 1 , further comprising forming a second thermal oxide film on the surface of the silicon carbide semiconductor layer between the polishing and the ion-implanting.
5. The method according to claim 1 , wherein the forming the first thermal oxide film is performed in an atmosphere containing water vapor.
6. The method according to claim 1 , further comprising performing shape inspection for the surface of the silicon carbide semiconductor layer after the polishing and before the ion-implanting impurities.
7. The method according to claim 1 , wherein a growth film thickness in the growing epitaxially the silicon carbide semiconductor layer is set to a film thickness obtained by adding a thickness expected to reduce in the polishing to a designed film thickness of the semiconductor device.
8. The method according to claim 4 , wherein the forming the second thermal oxide film is performed in an atmosphere containing water vapor.