A high linearity bandgap engineered transistor device is provided. In one example configuration, the device generally includes a substrate and an oxide layer formed on the substrate. The device further includes a wide-bandgap body material formed between a portion of the oxide layer and a gate dielectric layer. The wide-bandgap body material has an energy bandgap of 1.35 eV or higher and is lattice matched to the substrate. The device further includes a source-drain material formed on the oxide layer adjacent to the wide-bandgap body material so as to define a hetero-structure interface where the source-drain material contacts the wide-bandgap body material. The wide-bandgap body material is also lattice matched to the source-drain material. The device further includes a gate material formed over the gate dielectric layer. Other features and variations will be apparent in light of this disclosure.