A semiconductor device includes a gate structure on a substrate. The gate structure includes a first gate insulation pattern, a conductive pattern for controlling a threshold voltage, a first gate electrode and a first mask sequentially stacked. A dummy gate structure is spaced apart from the gate electrode. The dummy gate structure includes a first stressor pattern including titanium oxide. Source/drain regions are adjacent to the gate structure. The source/drain regions are doped with p-type impurities. The first stressor pattern may apply a stress onto the channel region of a transistor, and consequently the transistor having good electrical characteristics may be obtained.

A semiconductor device includes: a substrate; a gate structure on the substrate; and an epitaxial layer in the substrate adjacent to the gate structure, in which the epitaxial layer includes a planar surface and protrusions adjacent to two sides of the planar surface. Preferably, a contact plug is embedded in part of the epitaxial layer, and a silicide is disposed under the contact plug, in which a bottom surface of the silicide includes an arc.

A method of making a semiconductor device includes forming a source/drain region on a substrate; disposing a gate stack on the substrate and adjacent to the source/drain region, the gate stack including a gate spacer along a sidewall of the gate stack; disposing an inter-level dielectric (ILD) layer on the source/drain region and the gate stack; removing a portion of the ILD layer on the source/drain region to form a source/drain contact pattern; filling the source/drain contact pattern with a layer of silicon material, the layer of silicon material being in contact with the source/drain region and in contact with the gate spacer; depositing a metallic layer over the first layer of silicon material; and performing a silicidation process to form a source/drain contact including a silicide.

A three-dimensional transistor includes a semiconductor substrate, a fin coupled to the substrate, the fin including an active region across a top portion thereof, the active region including a source, a drain and a channel region therebetween. The transistor further includes a gate situated above the channel region, and a gate contact situated in the active region, no portion thereof being electrically coupled to the source or drain. The transistor is achieved by removing a portion of the source/drain contact situated beneath the gate contact during fabrication.

A method for fabricating a semiconductor device comprises forming a replacement gate structure on a semiconductor layer of a substrate. The replacement gate structure at least including a polysilicon layer. After forming the replacement gate structure, a gate spacer is formed on the replacement gate structure. Atoms are implanted in an upper portion of the polysilicon layer. The implanting expands the upper portion of the polysilicon layer and a corresponding upper portion of the gate spacer in at least a lateral direction beyond a lower portion of the polysilicon layer and a lower portion of the spacer, respectively. After the atoms have been implanted, the polysilicon layer is removed to form a gate cavity. A metal gate stack is formed within the gate cavity. The metal gate stack includes an upper portion having a width that is greater than a width of a lower portion of the metal gate stack.

A method for fabricating a semiconductor device comprises forming a replacement gate structure on a semiconductor layer of a substrate. The replacement gate structure at least including a polysilicon layer. After forming the replacement gate structure, a gate spacer is formed on the replacement gate structure. Atoms are implanted in an upper portion of the polysilicon layer. The implanting expands the upper portion of the polysilicon layer and a corresponding upper portion of the gate spacer in at least a lateral direction beyond a lower portion of the polysilicon layer and a lower portion of the spacer, respectively. After the atoms have been implanted, the polysilicon layer is removed to form a gate cavity. A metal gate stack is formed within the gate cavity. The metal gate stack includes an upper portion having a width that is greater than a width of a lower portion of the metal gate stack.

A semiconductor device includes a gate arranged on a substrate; a source/drain formed on the substrate adjacent to the gate; a source/drain contact extending from the source/drain and through an interlayer dielectric (ILD) over the source/drain, a portion of the source/drain positioned adjacent to the source/drain contact; and a silicide positioned along a sidewall of the source/drain contact between the portion of the source/drain and the source/drain contact, and along an endwall of the source/drain contact between the source/drain contact and the substrate.

A semiconductor device includes first and second fins on first and second regions of a substrate, a first trench overlapping a vertical end portion of the first fin and including first upper and lower portions, the first upper and lower portions separated by an upper surface of the first fin, a second trench overlapping a vertical end portion of the second fin and including second upper and lower portions separated by an upper surface of the second fin, a first dummy gate electrode including first metal oxide and filling layers, the first metal oxide layer filling the first lower portion of the first trench and is along a sidewall of the first upper portion of the first trench, and a second dummy gate electrode filling the second trench and including second metal oxide and filling layers, the second metal oxide layer extending along sidewalls of the second trench.

Embodiments of the present invention provide a structure and method of minimizing stress relaxation during fin formation. Embodiments may involve forming a looped spacer on an upper surface of a substrate and adjacent to at least a sidewall of a mandrel. The mandrel may be removed, leaving the looped spacer on the substrate. An exposed portion of the substrate may be removed to form a looped fin below the looped spacer. The spacer may be removed, leaving a looped fin. A looped fin formation may reduce stress relaxation compared to conventional fin formation methods. Embodiments may include forming a gate over a looped portion of a looped fin. Securing a looped portion in position with a gate may decrease stress relaxation in the fin. Thus, a looped fin with a looped portion of the looped fin under a gate may have substantially reduced stress relaxation compared to a conventional fin.

A semiconductor device in which sufficient stress can be applied to a channel region due to lattice constant differences.