A semiconductor device structure is provided. The semiconductor device structure includes a semiconductor substrate. The semiconductor device structure includes a gate stack over the semiconductor substrate. The gate stack includes a first insulating layer, a first layer, a second layer, a second insulating layer, and a gate electrode. The first insulating layer separates the semiconductor substrate from the first layer. The second layer is between the first layer and the second insulating layer. The gate electrode is over the second insulating layer. There is a P-N junction between the first layer and the second layer. The semiconductor device structure includes a first doped region and a second doped region in the semiconductor substrate. The first layer, the first doped region, and the second doped region have a first type conductivity, which is opposite to a second type conductivity of the second layer.