Abstract: A method of forming a semiconductor device includes: forming a fin protruding above a substrate; forming a gate layer over the fin; and patterning the gate layer in a plasma etching tool using a plasma etching process to form a gate over the fin, where patterning the gate layer includes: turning on and off a top radio frequency (RF) source of the plasma etching tool alternately during the plasma etching process; and turning on and off a bottom RF source of the plasma etching tool alternately during the plasma etching process, where there is a timing offset between first time instants when the top RF source is turned on and respective second time instants when the bottom RF source is turned on.

Abstract: A method of forming a semiconductor device includes: forming a fin protruding above a substrate; forming a gate layer over the fin; and patterning the gate layer in a plasma etching tool using a plasma etching process to form a gate over the fin, where patterning the gate layer includes: turning on and off a top radio frequency (RF) source of the plasma etching tool alternately during the plasma etching process; and turning on and off a bottom RF source of the plasma etching tool alternately during the plasma etching process, where there is a timing offset between first time instants when the top RF source is turned on and respective second time instants when the bottom RF source is turned on.

Abstract: A semiconductor device includes a fin structure protruding from an isolation insulating layer disposed over a substrate and having a channel region, a source/drain region disposed over the substrate, a gate dielectric layer disposed on the channel region, and a gate electrode layer disposed on the gate dielectric layer. The gate electrode includes a lower portion below a level of a top of the channel region and above an upper surface of the isolation insulating layer, and a width of the lower portion is not constant.

Abstract: A semiconductor device includes a fin structure protruding from an isolation insulating layer disposed over a substrate and having a channel region, a source/drain region disposed over the substrate, a gate dielectric layer disposed on the channel region, and a gate electrode layer disposed on the gate dielectric layer. The gate electrode includes a lower portion below a level of a top of the channel region and above an upper surface of the isolation insulating layer, and a width of the lower portion is not constant.

Abstract: A method includes forming a semiconductor fin extending a first height above a substrate, forming a dummy dielectric material over the semiconductor fin and over the substrate, forming a dummy gate material over the dummy dielectric material, the dummy gate material extending a second height above the substrate, etching the dummy gate material using multiple etching processes to form a dummy gate stack, wherein each etching process of the multiple etching processes is a different etching process, wherein the dummy gate stack has a first width at the first height, and wherein the dummy gate stack has a second width at the second height that is different from the first width.

Abstract: A semiconductor device includes first and second fin active regions extruding from a substrate, where the first and second fin active regions are separated by an isolation feature. The semiconductor includes a first gate stack disposed on the first fin active region and a second gate stack disposed on the second fin active region. The semiconductor device includes first source/drain features formed on the first fin active region, second source/drain features formed on the second fin active region, and a dielectric layer disposed along sidewalls of the first fin active region but not along sidewalls of the second fin active region. The first source/drain features extend vertically into the first fin active region at a first depth, the second source/drain features extend vertically into the second fin active region at a second depth, and the first depth is greater than the second depth.

Abstract: A method includes forming a semiconductor fin extending a first height above a substrate, forming a dummy dielectric material over the semiconductor fin and over the substrate, forming a dummy gate material over the dummy dielectric material, the dummy gate material extending a second height above the substrate, etching the dummy gate material using multiple etching processes to form a dummy gate stack, wherein each etching process of the multiple etching processes is a different etching process, wherein the dummy gate stack has a first width at the first height, and wherein the dummy gate stack has a second width at the second height that is different from the first width.

Abstract: A method for forming a semiconductor memory structure is provided. The method includes forming a stack over a substrate, and the stack includes first dielectric layers and second dielectric layers vertically alternately arranged. The method also includes forming first dielectric pillars through the stack, and etching the stack to form first trenches. Sidewalls of the first dielectric pillars are exposed from the first trenches. The method also includes removing the first dielectric pillars to form through holes, removing the second dielectric layers of the stack to form gaps between the first dielectric layers, and forming first conductive lines in the gaps.

Abstract: A method includes forming a fin structure on the substrate, wherein the fin structure includes a first fin active region; a second fin active region; and an isolation feature separating the first and second fin active regions; forming a first gate stack on the first fin active region and a second gate stack on the second fin active region; performing a first recessing process to a first source/drain region of the first fin active region by a first dry etch; performing a first epitaxial growth to form a first source/drain feature on the first source/drain region; performing a fin sidewall pull back (FSWPB) process to remove a dielectric layer on the second fin active region; and performing a second epitaxial growth to form a second source/drain feature on a second source/drain region of the second fin active region.

Abstract: A method of forming a semiconductor device includes: forming a fin protruding above a substrate; forming a gate layer over the fin; and patterning the gate layer in a plasma etching tool using a plasma etching process to form a gate over the fin, where patterning the gate layer includes: turning on and off a top radio frequency (RF) source of the plasma etching tool alternately during the plasma etching process; and turning on and off a bottom RF source of the plasma etching tool alternately during the plasma etching process, where there is a timing offset between first time instants when the top RF source is turned on and respective second time instants when the bottom RF source is turned on.

Abstract: A method of forming a semiconductor device includes: forming a fin protruding above a substrate; forming a gate layer over the fin; and patterning the gate layer in a plasma etching tool using a plasma etching process to form a gate over the fin, where patterning the gate layer includes: turning on and off a top radio frequency (RF) source of the plasma etching tool alternately during the plasma etching process; and turning on and off a bottom RF source of the plasma etching tool alternately during the plasma etching process, where there is a timing offset between first time instants when the top RF source is turned on and respective second time instants when the bottom RF source is turned on.

Abstract: A semiconductor device includes a fin structure protruding from an isolation insulating layer disposed over a substrate and having a channel region, a source/drain region disposed over the substrate, a gate dielectric layer disposed on the channel region, and a gate electrode layer disposed on the gate dielectric layer. The gate electrode includes a lower portion below a level of a top of the channel region and above an upper surface of the isolation insulating layer, and a width of the lower portion is not constant.

Abstract: A semiconductor device includes a fin structure protruding from an isolation insulating layer disposed over a substrate and having a channel region, a source/drain region disposed over the substrate, a gate dielectric layer disposed on the channel region, and a gate electrode layer disposed on the gate dielectric layer. The gate electrode includes a lower portion below a level of a top of the channel region and above an upper surface of the isolation insulating layer, and a width of the lower portion is not constant.

Abstract: A semiconductor device includes a fin structure protruding from an isolation insulating layer disposed over a substrate and having a channel region, a source/drain region disposed over the substrate, a gate dielectric layer disposed on the channel region, and a gate electrode layer disposed on the gate dielectric layer. The gate electrode includes a lower portion below a level of a top of the channel region and above an upper surface of the isolation insulating layer, and a width of the lower portion is not constant.

Abstract: A method of forming a semiconductor device includes: forming a fin protruding above a substrate; forming a gate layer over the fin; and patterning the gate layer in a plasma etching tool using a plasma etching process to form a gate over the fin, where patterning the gate layer includes: turning on and off a top radio frequency (RF) source of the plasma etching tool alternately during the plasma etching process; and turning on and off a bottom RF source of the plasma etching tool alternately during the plasma etching process, where there is a timing offset between first time instants when the top RF source is turned on and respective second time instants when the bottom RF source is turned on.

Abstract: A method includes etching a semiconductor substrate to form a first trench and a second trench. A remaining portion of the semiconductor substrate is left between the first trench and the second trench as a semiconductor region. A doped dielectric layer is formed on sidewalls of the semiconductor region and over a top surface of the semiconductor region. The doped dielectric layer includes a dopant. The first trench and the second trench are filled with a dielectric material. An anneal is then performed, and a p-type dopant or an n-type dopant in the doped dielectric layer is diffused into the semiconductor region to form a diffused semiconductor region.

Abstract: A method includes etching a semiconductor substrate to form a first trench and a second trench. A remaining portion of the semiconductor substrate is left between the first trench and the second trench as a semiconductor region. A doped dielectric layer is formed on sidewalls of the semiconductor region and over a top surface of the semiconductor region. The doped dielectric layer includes a dopant. The first trench and the second trench are filled with a dielectric material. An anneal is then performed, and a p-type dopant or an n-type dopant in the doped dielectric layer is diffused into the semiconductor region to form a diffused semiconductor region.

Abstract: A method includes forming a fin structure on the substrate, wherein the fin structure includes a first fin active region; a second fin active region; and an isolation feature separating the first and second fin active regions; forming a first gate stack on the first fin active region and a second gate stack on the second fin active region; performing a first recessing process to a first source/drain region of the first fin active region by a first dry etch; performing a first epitaxial growth to form a first source/drain feature on the first source/drain region; performing a fin sidewall pull back (FSWPB) process to remove a dielectric layer on the second fin active region; and performing a second epitaxial growth to form a second source/drain feature on a second source/drain region of the second fin active region.

Abstract: A method includes forming a fin structure on the substrate, wherein the fin structure includes a first fin active region; a second fin active region; and an isolation feature separating the first and second fin active regions; forming a first gate stack on the first fin active region and a second gate stack on the second fin active region; performing a first recessing process to a first source/drain region of the first fin active region by a first dry etch; performing a first epitaxial growth to form a first source/drain feature on the first source/drain region; performing a fin sidewall pull back (FSWPB) process to remove a dielectric layer on the second fin active region; and performing a second epitaxial growth to form a second source/drain feature on a second source/drain region of the second fin active region.

Abstract: A method includes forming a semiconductor fin extending a first height above a substrate, forming a dummy dielectric material over the semiconductor fin and over the substrate, forming a dummy gate material over the dummy dielectric material, the dummy gate material extending a second height above the substrate, etching the dummy gate material using multiple etching processes to form a dummy gate stack, wherein each etching process of the multiple etching processes is a different etching process, wherein the dummy gate stack has a first width at the first height, and wherein the dummy gate stack has a second width at the second height that is different from the first width.