Abstract: A method includes forming a first transistor, which includes forming a first gate dielectric layer over a first channel region in a substrate and forming a first work-function layer over the first gate dielectric layer, wherein forming the first work-function layer includes depositing a work-function material using first process conditions to form the work-function material having a first proportion of different crystalline orientations and forming a second transistor, which includes forming a second gate dielectric layer over a second channel region in the substrate and forming a second work-function layer over the second gate dielectric layer, wherein forming the second work-function layer includes depositing the work-function material using second process conditions to form the work-function material having a second proportion of different crystalline orientations.

Abstract: A semiconductor device includes a substrate, a gate stack, and epitaxy structures. The substrate has a P-type region. The gate stack is over the P-type region of the substrate and includes a gate dielectric layer, a bottom work function (WF) metal layer, a top WF metal layer, and a filling metal. The bottom WF metal layer is over the gate dielectric layer. The top WF metal layer is over and in contact with the bottom WF metal layer. Dipoles are formed between the top WF metal layer and the bottom WF metal layer, and the dipoles direct from the bottom WF metal layer to the top WF metal layer. The filling metal is over the top WF metal layer. The epitaxy structures are over the P-type region of the substrate and on opposite sides of the gate stack.

Abstract: A semiconductor device includes a substrate, a gate stack, and epitaxy structures. The substrate has a P-type region. The gate stack is over the P-type region of the substrate and includes a gate dielectric layer, a bottom work function (WF) metal layer, a top WF metal layer, and a filling metal. The bottom WF metal layer is over the gate dielectric layer. The top WF metal layer is over and in contact with the bottom WF metal layer. Dipoles are formed between the top WF metal layer and the bottom WF metal layer, and the dipoles direct from the bottom WF metal layer to the top WF metal layer. The filling metal is over the top WF metal layer. The epitaxy structures are over the P-type region of the substrate and on opposite sides of the gate stack.

Abstract: A method includes forming a first transistor, which includes forming a first gate dielectric layer over a first channel region in a substrate and forming a first work-function layer over the first gate dielectric layer, wherein forming the first work-function layer includes depositing a work-function material using first process conditions to form the work-function material having a first proportion of different crystalline orientations and forming a second transistor, which includes forming a second gate dielectric layer over a second channel region in the substrate and forming a second work-function layer over the second gate dielectric layer, wherein forming the second work-function layer includes depositing the work-function material using second process conditions to form the work-function material having a second proportion of different crystalline orientations.

Abstract: A method includes forming a first transistor, which includes forming a first gate dielectric layer over a first channel region in a substrate and forming a first work-function layer over the first gate dielectric layer, wherein forming the first work-function layer includes depositing a work-function material using first process conditions to form the work-function material having a first proportion of different crystalline orientations and forming a second transistor, which includes forming a second gate dielectric layer over a second channel region in the substrate and forming a second work-function layer over the second gate dielectric layer, wherein forming the second work-function layer includes depositing the work-function material using second process conditions to form the work-function material having a second proportion of different crystalline orientations.

Abstract: A semiconductor device includes a substrate, a gate stack, and epitaxy structures. The substrate has a P-type region. The gate stack is over the P-type region of the substrate and includes a gate dielectric layer, a bottom work function (WF) metal layer, a top WF metal layer, and a filling metal. The bottom WF metal layer is over the gate dielectric layer. The top WF metal layer is over and in contact with the bottom WF metal layer. Dipoles are formed between the top WF metal layer and the bottom WF metal layer, and the dipoles direct from the bottom WF metal layer to the top WF metal layer. The filling metal is over the top WF metal layer. The epitaxy structures are over the P-type region of the substrate and on opposite sides of the gate stack.

Abstract: A semiconductor device includes a substrate, a gate stack, and an epitaxy structure. The gate stack over the substrate and includes a gate dielectric layer, a bottom work function (WF) metal layer, a top WF metal layer, and a filling metal. The bottom WF metal layer is over the gate dielectric layer. The top WF metal layer is over and in contact with the bottom WF metal layer. At least one of the top and bottom WF metal layers includes dopants, and the top WF metal layer is thicker than the bottom WF metal layer. The filling metal is over the top WF metal layer. The epitaxy structure is over the substrate and adjacent the gate stack.

Abstract: A semiconductor device includes a substrate, a gate stack, and an epitaxy structure. The gate stack over the substrate and includes a gate dielectric layer, a bottom work function (WF) metal layer, a top WF metal layer, and a filling metal. The bottom WF metal layer is over the gate dielectric layer. The top WF metal layer is over and in contact with the bottom WF metal layer. At least one of the top and bottom WF metal layers includes dopants, and the top WF metal layer is thicker than the bottom WF metal layer. The filling metal is over the top WF metal layer. The epitaxy structure is over the substrate and adjacent the gate stack.

Abstract: A method includes forming a first transistor, which includes forming a first gate dielectric layer over a first channel region in a substrate and forming a first work-function layer over the first gate dielectric layer, wherein forming the first work-function layer includes depositing a work-function material using first process conditions to form the work-function material having a first proportion of different crystalline orientations and forming a second transistor, which includes forming a second gate dielectric layer over a second channel region in the substrate and forming a second work-function layer over the second gate dielectric layer, wherein forming the second work-function layer includes depositing the work-function material using second process conditions to form the work-function material having a second proportion of different crystalline orientations.

Abstract: A method includes forming a first transistor, which includes forming a first gate dielectric layer over a first channel region in a substrate and forming a first work-function layer over the first gate dielectric layer, wherein forming the first work-function layer includes depositing a work-function material using first process conditions to form the work-function material having a first proportion of different crystalline orientations and forming a second transistor, which includes forming a second gate dielectric layer over a second channel region in the substrate and forming a second work-function layer over the second gate dielectric layer, wherein forming the second work-function layer includes depositing the work-function material using second process conditions to form the work-function material having a second proportion of different crystalline orientations.

Abstract: A method includes forming a first transistor, which includes forming a first gate dielectric layer over a first channel region in a substrate and forming a first work-function layer over the first gate dielectric layer, wherein forming the first work-function layer includes depositing a work-function material using first process conditions to form the work-function material having a first proportion of different crystalline orientations and forming a second transistor, which includes forming a second gate dielectric layer over a second channel region in the substrate and forming a second work-function layer over the second gate dielectric layer, wherein forming the second work-function layer includes depositing the work-function material using second process conditions to form the work-function material having a second proportion of different crystalline orientations.