Described herein are transistor devices formed using perovskite gate dielectrics. In one example, a transistor includes a high-k perovskite dielectric material between a gate electrode and a thin film semiconductor channel. In another example, four-terminal transistor includes a semiconductor channel, a gate stack that includes a perovskite dielectric layer on one side of the channel, and a body electrode on an opposite side of the channel. The body electrode adjusts a threshold voltage of the transistor.