摘要 |
Various embodiments provide methods for fabricating dual supply voltage CMOS devices with a desired I/O transistor threshold voltage. The dual supply voltage CMOS devices can be fabricated in a semiconductor substrate that includes isolated regions for a logic NMOS transistor, a logic PMOS transistor, an I/O NMOS transistor, and an I/O PMOS transistor. Specifically, the fabrication can first set and/or adjust the threshold voltage (VT) of each of the I/O NMOS transistor and the I/O PMOS transistor to a desired level. Logic NMOS and logic PMOS transistors can then be formed with I/O NMOS and I/O PMOS transistors masked without affecting the set/adjusted VT of the I/O transistors. |