An IC structure includes a first transistor, a second transistor, a dielectric fin, a dielectric cap, a backside metal structure, and a source/drain contact. The first transistor includes a first channel region, a first gate structure, and first source/drain features disposed on opposite sides of the first gate structure. The second transistor includes a second channel region, a second gate structure, and second source/drain features disposed on opposite sides of the second gate structure. The dielectric fin is disposed between the first and second transistors. The dielectric cap interfaces a backside surface of the dielectric fin. The source/drain contact abuts the dielectric fin and is electrically coupled to a first one of the first source/drain features by way of a silicide layer and electrically coupled to the backside metal rail by way of physical contact established by the source/drain contact and the backside metal rail.

There is provided a semiconductor device capable of capable of improving element performance and reliability. A semiconductor device includes a lower conductive pattern disposed on a substrate, an upper conductive pattern disposed on the lower conductive pattern, and a first plug pattern disposed between the lower conductive pattern and the upper conductive pattern and connected to the lower conductive pattern and the upper conductive pattern. The first plug pattern includes a first barrier pattern that defines a first plug recess and a first plug metal pattern that fills the first plug recess, and the first plug metal pattern includes a first molybdenum pattern and a first tungsten pattern disposed on the first molybdenum pattern.

Generally, the present disclosure provides example embodiments relating to conductive features, such as metal contacts, vias, lines, etc., and methods for forming those conductive features. In a method embodiment, a dielectric layer is formed on a semiconductor substrate. The semiconductor substrate has a source/drain region. An opening is formed through the dielectric layer to the source/drain region. A silicide region is formed on the source/drain region and a barrier layer is formed in the opening along sidewalls of the dielectric layer by a same Plasma-Enhance Chemical Vapor Deposition (PECVD) process.

Devices and methods that include for configuring a profile of a liner layer before filling an opening disposed over a semiconductor substrate. The liner layer has a first thickness at the bottom of the opening and a second thickness a top of the opening, the second thickness being smaller that the first thickness. In an embodiment, the filled opening provides a contact structure.

Microelectronic deviceshaving at least one conductive contact structure adjacent a silicide regionare formed using methods that avoid unintentional contact expansion and contact reduction. A first metal nitride liner is formed in a contact opening, and an exposed surface of a polysilicon structure is thereafter treated (e.g., cleaned and dried) in preparation for formation of a silicide region. During the pretreatments (e.g., cleaning and drying), neighboring dielectric material is protected by the presence of the metal nitride liner, inhibiting expansion of the contact opening. After forming the silicide region, a second metal nitride liner is formed on the silicide region before a conductive material is formed to fill the contact opening and form a conductive contact structure (e.g., a memory cell contact structure, a peripheral contact structure).

A semiconductor structure includes a fin structure formed over a substrate. The structure also includes a gate structure formed across the fin structure. The structure also includes source/drain epitaxial structures formed on opposite sides of the gate structure. The structure also includes an inter-layer dielectric (ILD) structure formed over the gate structure. The structure also includes a contact blocking structure formed through the ILD structure over the source/drain epitaxial structure. A lower portion of the contact blocking structure is surrounded by an air gap, and the air gap is covered by a portion of the ILD structure.

In a method for producing structured metallic contacts on a semiconductor substrate, in one embodiment a layer sequence consisting of multiple metallic contact materials is deposited on the entire surface of the semiconductor substrate, and a further metallic contact material is applied on the layer sequence in predetermined contact regions. Then, the layer sequence in the contact regions undergoes a thermal treatment to form a low impedance contact from a Schottky contact. The thermal treatment is carried out by scanning the layer sequence with a laser beam. In the method, the wavelength of the laser beam, the metallic contact material of the topmost layer of the layer sequence and the further metallic contact material are tuned to each other in such a way that the metallic contact material of the topmost layer of the layer sequence has a reflectivity for the laser beam that is 1.3 times higher than that of the further metallic contact material. This results in a self-adjusting thermal treatment without the need for an additional protective mask.