Patent ID: 8686514

Claim:
A field effect transistor device including: a first conductive channel disposed on a substrate; a second conductive channel disposed on the substrate; a third conductive channel disposed on the substrate; a first gate stack formed circumferentially around the first conductive channel, the first gate stack including a metallic layer having a first oxygen content; a second gate stack a formed circumferentially around the second conductive channel, the second gate stack including a metallic layer having a second oxygen content; a third gate stack a formed circumferentially around the third conductive channel, the third gate stack including a metallic layer having a third oxygen content; an ion doped source region connected to the first conductive channel, the second conductive channel, and the third conductive channel; and an ion doped drain region connected to the first conductive channel, the second conductive channel, and the third conductive channel, wherein the first oxygen content is greater than the second oxygen content, which is greater than the third oxygen content, and wherein a threshold voltage of a first device defined by the first gate stack is dissimilar from a threshold voltage of a second device defined by the second gate stack, which is dissimilar from a threshold voltage of a third device defined by the third gate stack.