Semiconductor devices and methods of manufacturing thereof

A semiconductor device, comprising:

• a plurality of semiconductor layers vertically spaced from one another, wherein the plurality of semiconductor layers each extend along a first lateral direction;
• a metal gate structure extending along a second lateral direction and comprising a plurality of sections;
• a plurality of pairs of inner spacers, each of the pairs of inner spacers respectively disposed next to ends of a corresponding one of the plurality of sections;
• and
• a pair of source/drain structures in contact with ends of each of the plurality of semiconductor layers, respectively,
• wherein the plurality of semiconductor layers form a stack having an asymmetrical bow-shaped sidewall.

A semiconductor device, comprising:

• a plurality of semiconductor layers vertically spaced from one another, wherein the plurality of semiconductor layers each extend along a first lateral direction;
• a plurality of dielectric layers, each dielectric layer of the plurality of dielectric layers disposed vertically adjacent to a semiconductor layer of the plurality of semiconductor layers;
• a metal gate structure extending along a second lateral direction and comprising a plurality of sections;
• and
• a plurality of pairs of inner spacers, each of the pairs of inner spacers respectively disposed next to ends of a corresponding one of the plurality of sections,
• wherein the plurality of semiconductor layers form a stack having an upper portion and a lower portion, wherein the upper portion has a curved sidewall and the lower portion has a sidewall extending in a direction different than the second lateral direction.