A method comprises forming a gate structure over a semiconductor substrate; etching back the gate structure; forming a gate dielectric cap over the etched back gate structure; depositing an etch-resistant layer over the gate dielectric cap; depositing a contact etch stop layer over the gate dielectric cap and an interlayer dielectric (ILD) layer over the contact etch stop layer; performing a first etching process to form a gate contact opening extending through the ILD layer and terminating prior to reaching the etch-resistant layer; performing a second etching process to deepen the gate contact opening, wherein the second etching process etches the etch-resistant layer at a slower etch rate than etching the contact etch stop layer; and forming a gate contact in the deepened gate contact opening.

Methods for forming a semiconductor structure and semiconductor structures are described. The method comprises patterning a substrate to form a first opening and a second opening, the substrate comprising an n transistor and a p transistor, the first opening over the n transistor and the second opening over the p transistor; pre-cleaning the substrate; depositing a titanium silicide (TiSi) layer on the n transistor and on the p transistor by plasma-enhanced chemical vapor deposition (PECVD); optionally depositing a first barrier layer on the titanium silicide (TiSi) layer and selectively removing the first barrier layer from the p transistor; selectively forming a molybdenum silicide (MoSi) layer on the titanium silicide (TiSi) layer on the n transistor and the p transistor; forming a second barrier layer on the molybdenum silicide (MoSi) layer; and annealing the semiconductor structure. The method may be performed in a processing chamber without breaking vacuum.

Semiconductor device structures with a gate structure having different profiles at different portions of the gate structure may include a fin structure on a substrate, a source/drain structure on the fin structure, and a gate structure over the fin structure and along a sidewall of the fin. The source/drain structure is proximate the gate structure. The gate structure has a top portion having a first sidewall profile and a bottom portion having a second sidewall profile different from the first sidewall profile.

A method of forming a semiconductor device that includes forming a trench adjacent to a gate structure to expose a contact surface of one of a source region and a drain region. A sacrificial spacer may be formed on a sidewall of the trench and on a sidewall of the gate structure. A metal contact may then be formed in the trench to at least one of the source region and the drain region. The metal contact has a base width that is less than an upper surface width of the metal contact. The sacrificial spacer may be removed, and a substantially conformal dielectric material layer can be formed on sidewalls of the metal contact and the gate structure. Portions of the conformally dielectric material layer contact one another at a pinch off region to form an air gap between the metal contact and the gate structure.

A semiconductor structure and a forming method thereof are provided. The method includes: providing a substrate, a dummy spacer being formed on a side wall of the gate structure, a contact etch stop layer being formed on a side wall of the dummy spacer, and a source/drain doped area being formed in the substrate on two sides of the gate structure; forming a sacrificial dielectric layer above tops of the source/drain doped area and the gate structure; forming a source/drain plug running through the sacrificial dielectric layer; etching the sacrificial dielectric layer until a top of the dummy spacer is exposed; removing, after the top of the dummy spacer is exposed, the dummy spacer to form a gap between the contact etch stop layer and the side wall of the gate structure; and forming a top dielectric layer filling between the source/drain plugs.

The present disclosure provides a method for preparing a semiconductor device. The method includes forming a sacrificial source/drain structure over a first carrier substrate; forming a redistribution structure over the sacrificial source/drain structure;

attaching the redistribution structure to a second carrier substrate; removing the first carrier substrate after the redistribution structure is attached to the second carrier substrate; replacing the sacrificial source/drain structure with a first source/drain structure; forming a backside contact over and electrically connected to the first source/drain structure; and forming an interconnect part over the backside contact.

Integrated circuit transistor structures are disclosed that reduce n-type dopant diffusion, such as phosphorous or arsenic, from the source region and the drain region of a germanium n-MOS device into adjacent shallow trench isolation (STI) regions during fabrication. The n-MOS transistor device may include at least 75% germanium by atomic percentage. In an example embodiment, the structure includes an intervening diffusion barrier deposited between the n-MOS transistor and the STI region to provide dopant diffusion reduction. In some embodiments, the diffusion barrier may include silicon dioxide with carbon concentrations between 5 and 50% by atomic percentage. In some embodiments, the diffusion barrier may be deposited using chemical vapor deposition (CVD), atomic layer deposition (ALD), or physical vapor deposition (PVD) techniques to achieve a diffusion barrier thickness in the range of 1 to 5 nanometers.

A semiconductor device including a fin field effect transistor (fin-FET) includes active fins disposed on a substrate, isolation layers on both sides of the active fins, a gate structure formed to cross the active fins and the isolation layers, source/drain regions on the active fins on sidewalls of the gate structure, a first interlayer insulating layer on the isolation layers in contact with portions of the sidewalls of the gate structure and portions of surfaces of the source/drain regions, an etch stop layer configured to overlap the first interlayer insulating layer, the sidewalls of the gate structure, and the source/drain regions, and contact plugs formed to pass through the etch stop layer to contact the source/drain regions. The source/drain regions have main growth portions in contact with upper surfaces of the active fins.

Source/drain contacts between transistor gates with abbreviated inner spacers for improved contact area are disclosed. Related methods of fabricating source/drain contacts and abbreviated inner spacers are also disclosed. Inner spacers formed on sidewalls of the gates of adjacent transistors are abbreviated to reduce an amount of the space the inner spacers occupy on the source/drain region, increasing a critical dimension of the source/drain contact. Abbreviated inner spacers extend from a top of the gate over a portion of the sidewalls to provide leakage current protection but do not fully extend to the semiconductor substrate. As a result, the critical dimension of the source/drain contact can extend from a sidewall on a first gate to a sidewall on a second gate. A source/drain contact formed between gates with abbreviated inner spacers has a greater surface area in contact with the source/drain region providing decreased contact resistance.

A semiconductor device includes a flip flop cell. The flip flop cell is formed on a semiconductor substrate, includes a flip flop circuit, and comprises a scan mux circuit, a master latch circuit, a slave latch circuit, a clock driver circuit, and an output circuit. Each of the scan mux circuit, the master latch circuit, the slave latch circuit, the clock driver circuit, and the output circuit includes a plurality of active devices which together output a resulting signal for that circuit based on inputs, is a sub-circuit of the flip flop circuit, and occupies a continuously-bounded area of the flip flop circuit from a plan view. At least a first sub-circuit and a second sub-circuit of the sub-circuits overlap from the plan view in a first overlap region, the first overlap region including part of a first continuously-bounded area for the first sub-circuit and part of a second continuously-bounded area for the second sub-circuit.