Abstract
The invention relates to a semiconductor device and a manufacturing method thereof. The semiconductor device includes: a substrate; a first nitride semiconductor layer provided on the substrate; and a second nitride semiconductor layer provided on the first nitride semiconductor layer and having a band gap larger than a band gap of the first nitride semiconductor layer. The semiconductor device further includes: a first gate conductor disposed on the first region of the second nitride semiconductor layer; a first source electrode disposed on a first side of the first gate conductor; a first field plate disposed on a second side of the first gate conductor; and a capacitor having a first conductive layer and a second conductive layer, and disposed on the second region of the second nitride semiconductor layer. The first conductive layer of the capacitor and the first source electrode have a first material, and the second conductive layer of the capacitor and the first field plate have a second material.