Abstract: A transistor includes a gate structure that has a first gate dielectric layer and a second gate dielectric layer. The first gate dielectric layer is disposed over the substrate. The first gate dielectric layer contains a first type of dielectric material that has a first dielectric constant. The second gate dielectric layer is disposed over the first gate dielectric layer. The second gate dielectric layer contains a second type of dielectric material that has a second dielectric constant. The second dielectric constant is greater than the first dielectric constant. The first dielectric constant and the second dielectric constant are each greater than a dielectric constant of silicon oxide.

Abstract: A method includes receiving a workpiece having a first stack of semiconductor layers in a first region and a second stack of semiconductor layers in a second region; forming a first gate dielectric layer surrounding each layer of the first stack and a second gate dielectric layer surrounding each layer of the second stack; forming a first dipole layer surrounding the first gate dielectric layer and merging between vertically adjacent portions of the first gate dielectric layer, and a second dipole layer surrounding the second gate dielectric layer and merging between vertically adjacent portions of the second gate dielectric layer; removing the first dipole layer; after the removing of the first dipole layer, conducting a first annealing on the workpiece; removing a remaining portion of the second dipole layer; and forming a gate electrode layer in the first region and the second region.

Abstract: A semiconductor structure includes a substrate, a first transistor disposed over the substrate and including a first channel, a first interfacial layer over the first channel, a first gate dielectric layer over the first interfacial layer, and a first gate electrode layer over the first gate dielectric layer, and a second transistor disposed over the substrate and including a second channel, a second interfacial layer over the second channel, a second gate dielectric layer over the second interfacial layer, and a second gate electrode layer over the second gate dielectric layer. The first gate dielectric layer includes a first dipole material composition having a first maximum concentration at a half-thickness line of the first gate dielectric layer. The second gate dielectric layer includes a second dipole material composition having a second maximum concentration at a half-thickness line of the second gate dielectric layer and greater than the first maximum concentration.

Abstract: A device includes a semiconductor substrate, a fin structure on the semiconductor substrate, a gate structure on the fin structure, and a pair of source/drain features on both sides of the gate structure. The gate structure includes an interfacial layer on the fin structure, a gate dielectric layer on the interfacial layer, and a gate electrode layer of a conductive material on and directly contacting the gate dielectric layer. The gate dielectric layer includes nitrogen element.

Abstract: A transistor includes a gate structure that has a first gate dielectric layer and a second gate dielectric layer. The first gate dielectric layer is disposed over the substrate. The first gate dielectric layer contains a first type of dielectric material that has a first dielectric constant. The second gate dielectric layer is disposed over the first gate dielectric layer. The second gate dielectric layer contains a second type of dielectric material that has a second dielectric constant. The second dielectric constant is greater than the first dielectric constant. The first dielectric constant and the second dielectric constant are each greater than a dielectric constant of silicon oxide.

Abstract: A transistor includes a gate structure that has a first gate dielectric layer and a second gate dielectric layer. The first gate dielectric layer is disposed over the substrate. The first gate dielectric layer contains a first type of dielectric material that has a first dielectric constant. The second gate dielectric layer is disposed over the first gate dielectric layer. The second gate dielectric layer contains a second type of dielectric material that has a second dielectric constant. The second dielectric constant is greater than the first dielectric constant. The first dielectric constant and the second dielectric constant are each greater than a dielectric constant of silicon oxide.

Abstract: A method includes forming a dielectric layer on a semiconductor workpiece, forming a first patterned layer of a first dipole material on the dielectric layer, and performing a first thermal drive-in operation at a first temperature to form a diffusion feature in a first portion of the dielectric layer beneath the first patterned layer. The method also includes forming a second patterned layer of a second dipole material, where a first section of the second patterned layer is on the diffusion feature and a second section of the second patterned layer is offset from the diffusion feature. The method further includes performing a second thermal drive-in operation at a second temperature, where the second temperature is less than the first temperature. The method additionally includes forming a gate electrode layer on the dielectric layer.

Abstract: A semiconductor device includes a first semiconductor layer below a second semiconductor layer; first and second gate dielectric layers surrounding the first and the second semiconductor layers, respectively; and a gate electrode surrounding both the first and the second gate dielectric layers. The first gate dielectric layer has a first top section above the first semiconductor layer and a first bottom section below the first semiconductor layer. The second gate dielectric layer has a second top section above the second semiconductor layer and a second bottom section below the second semiconductor layer. The first top section has a first thickness. The second top section has a second thickness. The second thickness is greater than the first thickness.

Abstract: A semiconductor device includes a first semiconductor layer below a second semiconductor layer; first and second gate dielectric layers surrounding the first and the second semiconductor layers, respectively; and a gate electrode surrounding both the first and the second gate dielectric layers. The first gate dielectric layer has a first top section above the first semiconductor layer and a first bottom section below the first semiconductor layer. The second gate dielectric layer has a second top section above the second semiconductor layer and a second bottom section below the second semiconductor layer. The first top section has a first thickness. The second top section has a second thickness. The second thickness is greater than the first thickness.

Abstract: A method of forming a semiconductor device includes forming a fin over a substrate, the fin comprising alternately stacking first semiconductor layers and second semiconductor layers, removing the first semiconductor layers to form spaces each between the second semiconductor layers, forming a gate dielectric layer wrapping around each of the second semiconductor layers, forming a fluorine-containing layer on the gate dielectric layer, performing an anneal process to drive fluorine atoms from the fluorine-containing layer into the gate dielectric layer, removing the fluorine-containing layer, and forming a metal gate on the gate dielectric layer.

Abstract: Semiconductor device and the manufacturing method thereof are disclosed. An exemplary semiconductor device comprises a first semiconductor stack and a second semiconductor stack over a substrate, wherein each of the first and second semiconductor stacks includes semiconductor layers stacked up and separated from each other; a dummy spacer between the first and second semiconductor stacks, wherein the dummy spacer contacts a first sidewall of each semiconductor layer of the first and second semiconductor stacks; and a gate structure wrapping a second sidewall, a top surface, and a bottom surface of each semiconductor layer of the first and second semiconductor stacks.

Abstract: Semiconductor structures and methods are provided. An exemplary method according to the present disclosure includes providing a workpiece comprising a first channel member directly over a first region of a substrate and a second channel member directly over the first channel member, the first channel member being vertically spaced apart from the second channel member, conformally forming a dielectric layer over the workpiece, conformally depositing a dipole material layer over the dielectric layer, after the depositing of the dipole material layer, performing a thermal treatment process to the workpiece, after the performing of the thermal treatment process, selectively removing the dipole material layer, and forming a gate electrode layer over the dielectric layer.

Abstract: A transistor includes a gate structure that has a first gate dielectric layer and a second gate dielectric layer. The first gate dielectric layer is disposed over the substrate. The first gate dielectric layer contains a first type of dielectric material that has a first dielectric constant. The second gate dielectric layer is disposed over the first gate dielectric layer. The second gate dielectric layer contains a second type of dielectric material that has a second dielectric constant. The second dielectric constant is greater than the first dielectric constant. The first dielectric constant and the second dielectric constant are each greater than a dielectric constant of silicon oxide.

Abstract: Semiconductor device and the manufacturing method thereof are disclosed. An exemplary semiconductor device comprises a first semiconductor stack and a second semiconductor stack over a substrate, wherein each of the first and second semiconductor stacks includes semiconductor layers stacked up and separated from each other; a dummy spacer between the first and second semiconductor stacks, wherein the dummy spacer contacts a first sidewall of each semiconductor layer of the first and second semiconductor stacks; and a gate structure wrapping a second sidewall, a top surface, and a bottom surface of each semiconductor layer of the first and second semiconductor stacks.

Abstract: A method includes forming a first gate dielectric, a second gate dielectric, and a third gate dielectric over a first semiconductor region, a second semiconductor region, and a third semiconductor region, respectively. The method further includes depositing a first lanthanum-containing layer overlapping the first gate dielectric, and depositing a second lanthanum-containing layer overlapping the second gate dielectric. The second lanthanum-containing layer is thinner than the first lanthanum-containing layer. An anneal process is then performed to drive lanthanum in the first lanthanum-containing layer and the second lanthanum-containing layer into the first gate dielectric and the second gate dielectric, respectively. During the anneal process, the third gate dielectric is free from lanthanum-containing layers thereon.

Abstract: A semiconductor device includes a first semiconductor layer below a second semiconductor layer; first and second gate dielectric layers surrounding the first and the second semiconductor layers, respectively; and a gate electrode surrounding both the first and the second gate dielectric layers. The first gate dielectric layer has a first top section above the first semiconductor layer and a first bottom section below the first semiconductor layer. The second gate dielectric layer has a second top section above the second semiconductor layer and a second bottom section below the second semiconductor layer. The first top section has a first thickness. The second top section has a second thickness. The second thickness is greater than the first thickness.

Abstract: A method includes forming a first gate dielectric, a second gate dielectric, and a third gate dielectric over a first semiconductor region, a second semiconductor region, and a third semiconductor region, respectively. The method further includes depositing a first lanthanum-containing layer overlapping the first gate dielectric, and depositing a second lanthanum-containing layer overlapping the second gate dielectric. The second lanthanum-containing layer is thinner than the first lanthanum-containing layer. An anneal process is then performed to drive lanthanum in the first lanthanum-containing layer and the second lanthanum-containing layer into the first gate dielectric and the second gate dielectric, respectively. During the anneal process, the third gate dielectric is free from lanthanum-containing layers thereon.

Abstract: A semiconductor device includes a stack of semiconductor layers vertically arranged above a semiconductor base structure, a gate dielectric layer having portions each surrounding one of the semiconductor layers, and a gate electrode surrounding the gate dielectric layer. Each portion of the gate dielectric layer has a top section above the respective semiconductor layer and a bottom section below the semiconductor layer. The top section has a top thickness along a vertical direction perpendicular to a top surface of the semiconductor base structure; and the bottom section has a bottom thickness along the vertical direction. The top thickness is greater than the bottom thickness.

Abstract: A device includes a semiconductor substrate, a fin structure on the semiconductor substrate, a gate structure on the fin structure, and a pair of source/drain features on both sides of the gate structure. The gate structure includes an interfacial layer on the fin structure, a gate dielectric layer on the interfacial layer, and a gate electrode layer of a conductive material on and directly contacting the gate dielectric layer. The gate dielectric layer includes nitrogen element.

Abstract: A transistor includes a gate structure that has a first gate dielectric layer and a second gate dielectric layer. The first gate dielectric layer is disposed over the substrate. The first gate dielectric layer contains a first type of dielectric material that has a first dielectric constant. The second gate dielectric layer is disposed over the first gate dielectric layer. The second gate dielectric layer contains a second type of dielectric material that has a second dielectric constant. The second dielectric constant is greater than the first dielectric constant. The first dielectric constant and the second dielectric constant are each greater than a dielectric constant of silicon oxide.