Method for manufacturing silicon carbide semiconductor device

摘要

In a method for manufacturing a silicon carbide semiconductor device, a conductive layer is formed on a silicon carbide layer. The silicon carbide layer and the conductive layer react with each other thus forming an alloy layer formed of a reaction layer in contact with the silicon carbide layer and a silicide layer on the reaction layer. A carbon component is removed from the silicide layer. A portion of the silicide layer is removed using an acid thus exposing at least a portion of the reaction layer. An electrode layer is formed on an upper side of the exposed reaction layer.

主权项

1. A method for manufacturing a silicon carbide semiconductor device comprising the steps in the following order:
a conductive layer forming step where a conductive layer is formed on a silicon carbide layer; a heat treatment step where the silicon carbide layer and the conductive layer are made to react with each other thus forming a reaction layer which is in contact with the silicon carbide layer and a silicide layer which is present on the reaction layer; a first plasma ashing step where a carbon component which the silicide layer formed in the heat treatment step contains is removed; an etching step where at least a portion of the silicide layer is removed using an etchant which contains a hydrochloric acid, a nitric acid and a hydrofluoric acid thus exposing at least a portion of a surface of the reaction layer; and an electrode layer forming step where an electrode layer is formed on an upper side of the exposed reaction layer, wherein the method further comprises a second plasma ashing step where a carbon component which remains on the reaction layer is removed between the etching step and the electrode layer forming step.