Patent ID: 8294180
Filing Date: 2012-10-23
Classification: H01L

Abstract:
1. A pair of pMOS transistors, comprising: a first SiGe channel region on a first region of a silicon substrate, the first SiGe channel region having a first concentration of Ge; a second SiGe channel region on a second region of the silicon substrate, the second SiGe channel region having a second concentration of Ge, different than the first concentration of Ge; a gate insulator on the first and second SiGe channel regions; a first gate electrode on the gate insulator over the first SiGe channel region; a second gate electrode on the gate insulator over the second SiGe channel region, wherein the first gate electrode and the second gate electrode have a same mid-gap work function to provide a first of the pair of pMOS transistors with a threshold voltage that is different than a second of the pair of pMOS transistors; and a p-type doped source and drain on opposite sides of both the first and second gate electrodes.