A semiconductor device include a semiconductor substrate, a first trench electrode formed in the semiconductor substrate and having a first portion, a second trench electrode formed in the semiconductor substrate having a second portion facing the first portion, a floating layer of a first conductivity type formed around the first and second trench electrodes, a drift layer of a second conductivity type connected to the floating layer of the first conductivity type and formed between the first and second trench electrodes, an impurity layer of the first conductivity type connected to the drift layer of the second conductivity type and formed between the first and second trench electrodes, and a floating layer control gate having a portion located at least above the impurity layer of the first conductivity type.