The present application discloses a method for fabricating a semiconductor device. The method includes: providing a substrate including a plurality of first regions and second regions; forming a plurality of bit line contacts over the first regions of the substrate; forming a plurality of bit lines respectively over the plurality of bit line contacts; forming a plurality of capacitor contacts respectively over the second regions of the substrate; forming a plurality of capacitor plugs respectively over the plurality of capacitor contacts; forming a plurality of first spacers respectively over a plurality of protruding portions of the plurality of capacitor plugs, wherein a width of the first spacer is larger than a width of the capacitor plug; and forming a plurality of capacitor structures over the plurality of first spacers; wherein at least one of the plurality of bit lines is an undulating stripe extending between two adjacent capacitor contacts.

A semiconductor device includes a substrate including PMOSFET and NMOSFET regions, a first gate structure extending in a first direction and crossing the PMOSFET and NMOSFET regions, and a gate contact on and connected to the first gate structure, the gate contact being between the PMOSFET and NMOSFET regions, the gate contact including a first sub contact in contact with a top surface of the first gate structure, the first sub contact including a vertical extending portion extending vertically toward the substrate along one sidewall of the first gate structure, and a second sub contact spaced apart from the first gate structure, a top surface of the second sub contact being positioned at a same level as a top surface of the first sub contact.

A varactor transistor includes a semiconductor fin having a first conductivity type, a plurality of gate structures separated from each other and surrounding a portion of the semiconductor fin. The plurality of gates structures include a dummy gate structure on an edge of the semiconductor fin, and a first gate structure spaced apart from the dummy gate structure. The dummy gate structure and the gate structure each include a gate insulator layer on a surface portion of the semiconductor fin, a gate on the gate insulator layer, and a spacer on the gate. The varactor transistor also includes a raised source/drain region on the semiconductor fin and between the dummy gate structure and the first gate structure, the raised source/drain region and the gate of the dummy gate structure being electrically connected to a same potential.

An interconnect structure includes a substrate, a dielectric layer on the substrate, a metal interconnect layer in the dielectric layer and in contact with the substrate, the metal interconnect layer having an upper surface flush with an upper surface of the dielectric layer, and a graphene layer on the metal interconnect layer. The graphene layer insulates a metal from air and prevents the metal from being oxidized by oxygen in the air, thereby increasing the queue time for the CMP process and the device reliability.

An interconnect structure including a semiconductor structure on a semiconductor substrate, the semiconductor structure having a gate structure, shallow trench isolation and a source and a drain; a trench adjacent to the gate structure; a metal line adjacent to the gate structure and filling the trench, the metal line contacts one of the source and the drain; a gap in the metal line so as to create segments of the metal line; and a dielectric material filling the gap such that ends of the metal line abut the dielectric material wherein the ends of the metal line have a flat surface.

Middle-of-line (MOL) interconnects that facilitate reduced capacitance and/or resistance and corresponding techniques for forming the MOL interconnects are disclosed herein. An exemplary MOL interconnect structure includes a device-level contact disposed in a first insulator layer and a ruthenium structure disposed in a second insulator layer disposed over the first insulator layer. The device-level contact physically contacts an integrated circuit feature, and the ruthenium structure physically contacts the device-level contact. An air gap separates sidewalls of the ruthenium structure from the second insulator layer. A top surface of the ruthenium structure is lower than a top surface of the second insulator layer. A via disposed in a third insulator layer extends below the top surface of the second insulator layer to physically contact the ruthenium structure. A remainder of a dummy contact spacer layer may separate the first insulator layer and the second insulator layer.

A method for fabricating a semiconductor device is provided. A substrate having a dummy gate thereon is prepared. A spacer is disposed on a sidewall of the dummy gate. A source/drain region is disposed adjacent to the dummy gate. A sacrificial layer is then formed on the source/drain region. A cap layer is then formed on the sacrificial layer. A top surface of the cap layer is coplanar with a top surface of the dummy gate. A replacement metal gate (RMG) process is performed to transform the dummy gate into a replacement metal gate. An opening is then formed in the cap layer to expose a top surface of the sacrificial layer. The sacrificial layer is removed through the opening, thereby forming a lower contact hole exposing a top surface of the source/drain region. A lower contact plug is then formed in the lower contact hole.

A method for fabricating semiconductor device includes the steps of: forming a dielectric layer on a substrate; forming a stop layer between the dielectric layer and the substrate, wherein the stop layer contacts the substrate directly and the dielectric layer covers the top surface of the stop layer; forming an opening in the dielectric layer, wherein the dielectric layer comprises a damaged layer adjacent to the opening; forming a dielectric protective layer in the opening; forming a metal layer in the opening; removing the damaged layer and the dielectric protective layer to form a void, wherein the void exposes a top surface of the substrate; and forming a cap layer on and covering the dielectric layer, the void, and the metal layer.

Microelectronic devices include a stack structure of insulative structures vertically alternating with conductive structures and arranged in tiers forming opposing staircase structures. A polysilicon fill material substantially fills an opening (e.g., a high-aspect-ratio opening) between the opposing staircase structures. The polysilicon fill material may have non-compressive stress such that the stack structure may be partitioned into blocks without the blocks bending and without contacts—formed in at least one of the polysilicon fill material and the stack structure—deforming, misaligning, or forming electrical shorts with neighboring contacts.

An integrated circuit structure in which a gate overlies channel region in an active area of a first transistor. The first transistor includes a channel region, a source region and a drain region. A conductive contact is coupled to the drain region of the first transistor. A second transistor that includes a channel region, a source region a drain region is adjacent to the first transistor. The gate of the second transistor is spaced from the gate of the first transistor. A conductive via passes through an insulation layer to electrically connect to the gate of the second transistor. An expanded conductive via overlays both the conductive contact and the conductive via to electrically connect the drain of the first transistor to the gate of the second transistor.