In embodiments, a semiconductor device includes a high resistivity substrate, a transistor disposed on the high resistivity substrate, and a deep trench device isolation region disposed in the high resistivity substrate to surround the transistor. Particularly, the high resistivity substrate has a first conductive type, and a deep well region having a second conductive type is disposed in the high resistivity substrate. Further, a first well region having the first conductive type is disposed on the deep well region, and the transistor is disposed on the first well region.