A semiconductor device structure is provided. The semiconductor device structure includes a pair of source/drain features formed in a semiconductor substrate and a gate stack formed over a portion of the semiconductor substrate that is between the pair of source/drain features. The semiconductor device structure also includes gate spacers extend along opposing sidewalls of the gate stack and protrude above an upper surface of the gate stack. Additionally, the semiconductor device structure includes a first capping layer formed over the gate stack and spaced apart from the upper surface of the gate stack by a gap. Opposing sidewalls of the first capping layer are covered by portions of the gate spacers that protrude above the upper surface of the gate stack.

A semiconductor device structure is provided. The semiconductor device structure includes a pair of source/drain features formed in a semiconductor substrate and a gate stack formed over a portion of the semiconductor substrate that is between the pair of source/drain features. The semiconductor device structure also includes gate spacers extend along opposing sidewalls of the gate stack and protrude above an upper surface of the gate stack. Additionally, the semiconductor device structure includes a first capping layer formed over the gate stack and spaced apart from the upper surface of the gate stack by a gap. Opposing sidewalls of the first capping layer are covered by portions of the gate spacers that protrude above the upper surface of the gate stack.

A semiconductor structure and a method for forming the same are provided. The method for forming the semiconductor structure includes: providing a substrate; etching the substrate to form multiple active areas, trenches each positioned between adjacent active areas, and air gaps positioned below the active areas; and forming a filler layer filling at least each of the trenches.

A semiconductor device and a method of forming the same are provided. The method includes forming a sacrificial gate structure over an active region. A first spacer layer is formed along sidewalls and a top surface of the sacrificial gate structure. A first protection layer is formed over the first spacer layer. A second spacer layer is formed over the first protection layer. A third spacer layer is formed over the second spacer layer. The sacrificial gate structure is replaced with a replacement gate structure. The second spacer layer is removed to form an air gap between the first protection layer and the third spacer layer.

A semiconductor device and a method of forming the same are provided. The method includes forming a sacrificial gate structure over an active region. A first spacer layer is formed along sidewalls and a top surface of the sacrificial gate structure. A first protection layer is formed over the first spacer layer. A second spacer layer is formed over the first protection layer. A third spacer layer is formed over the second spacer layer. The sacrificial gate structure is replaced with a replacement gate structure. The second spacer layer is removed to form an air gap between the first protection layer and the third spacer layer.

A semiconductor device structure includes a dielectric layer, a first source/drain feature in contact with the dielectric layer, wherein the first source/drain feature comprises a first sidewall, and a second source/drain feature in contact with the dielectric layer and adjacent to the first source/drain feature, wherein the second source/drain feature comprises a second sidewall. The structure also includes an insulating layer disposed over the dielectric layer and between the first sidewall and the second sidewall, wherein the insulating layer comprises a first surface facing the first sidewall, a second surface facing the second sidewall, a third surface connecting the first surface and the second surface, and a fourth surface opposite the third surface. The structure includes a sealing material disposed between the first sidewall and the first surface, wherein the sealing material, the first sidewall, the first surface, and the dielectric layer are exposed to an air gap.

A semiconductor device structure includes a dielectric layer, a first source/drain feature in contact with the dielectric layer, wherein the first source/drain feature comprises a first sidewall, and a second source/drain feature in contact with the dielectric layer and adjacent to the first source/drain feature, wherein the second source/drain feature comprises a second sidewall. The structure also includes an insulating layer disposed over the dielectric layer and between the first sidewall and the second sidewall, wherein the insulating layer comprises a first surface facing the first sidewall, a second surface facing the second sidewall, a third surface connecting the first surface and the second surface, and a fourth surface opposite the third surface. The structure includes a sealing material disposed between the first sidewall and the first surface, wherein the sealing material, the first sidewall, the first surface, and the dielectric layer are exposed to an air gap.

The present disclosure relates to a semiconductor device with an air gap below a landing pad and a method for forming the semiconductor device. The semiconductor device includes a first lower plug and a second lower plug disposed over a semiconductor substrate. The semiconductor device also includes a first landing pad disposed over a top surface and upper sidewalls of the first lower plug, and a first upper plug disposed over the first landing pad and electrically connected to the first lower plug. A width of the first lower plug is greater than a width of the first upper plug. The semiconductor device further includes a dielectric layer disposed over the semiconductor substrate. The first lower plug, the second lower plug, the first landing pad and the first upper plug are disposed in the dielectric layer, and the dielectric layer includes an air gap disposed between the first lower plug and the second lower plug.

The present disclosure relates to a semiconductor device with an air gap below a landing pad and a method for forming the semiconductor device. The semiconductor device includes a first lower plug and a second lower plug disposed over a semiconductor substrate. The semiconductor device also includes a first landing pad disposed over a top surface and upper sidewalls of the first lower plug, and a first upper plug disposed over the first landing pad and electrically connected to the first lower plug. A width of the first lower plug is greater than a width of the first upper plug. The semiconductor device further includes a dielectric layer disposed over the semiconductor substrate. The first lower plug, the second lower plug, the first landing pad and the first upper plug are disposed in the dielectric layer, and the dielectric layer includes an air gap disposed between the first lower plug and the second lower plug.

A semiconductor structure and a method for forming a semiconductor structure are provided. The method includes: a substrate is provided; bit line contact holes spaced apart from each other, bit line contacts each in contact with a part of a respective one of the bit line contact holes, and bit line structures are formed on the substrate, where each of the bit line structures includes at least a conductive layer and an insulating cap layer, and the insulating cap layer is located on the conductive layer; first insulating layers completely filling the bit line contact holes are formed inside the bit line contact holes; and insulation structures with air interlayers are formed on two side walls of the bit line structures, where a height of each of the air interlayers is greater than a height of the conductive layer of each of the bit line structures.