An n-type SBTT and a manufacturing method thereof are provided. The SBTT includes a silicon layer, a gate, a double layer that has a rare-earth metal silicide layer and a transition metal silicide layer. The silicon layer has a channel region. The gate is formed in an overlapping manner on the channel region and has a gate dielectric layer on its interface with respect to the silicon layer. The double layer is formed as a source/drain that has the channel region interposed on the silicon layer.