| abstract |
A semiconductor device includes a substrate, a channel layer formed over the substrate, an active layer formed over the channel layer, and a gate structure formed over the active layer. The active layer is configured to cause a two dimensional electron gas (2DEG) to be formed in the channel layer along an interface between the channel layer and the active layer. The gate structure is configured to deplete the 2DEG under the gate structure. The active layer has a negatively charged region under the gate structure. The negatively charged region is configured to further deplete the 2DEG under the gate structure. |