A method comprises forming a gate structure between gate spacers; etching back the gate structure to fall below top ends of the gate spacers; forming a gate dielectric cap over the etched back gate structure; performing an ion implantation process to form a doped region in the gate dielectric cap; depositing a contact etch stop layer over the gate dielectric cap and an 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 doped region of the gate dielectric cap; performing a second etching process to deepen the gate contact opening, wherein the second etching process etches the doped region of the gate dielectric cap 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 processing a semiconductor substrate are proposed. An example of a method includes forming cavities in the semiconductor substrate by implanting ions through a first surface of the semiconductor substrate. The cavities define a separation layer in the semiconductor substrate. A semiconductor layer is formed on the first surface of the semiconductor substrate. Semiconductor device elements are formed in the semiconductor layer. The semiconductor substrate is separated along the separation layer into a first substrate part including the semiconductor layer and a second substrate part.

A method includes depositing an interlayer dielectric (ILD) over a source/drain region, implanting impurities into a portion of the ILD, recessing the portion of the ILD to form a trench, forming spacers on sidewalls of the trench, the spacers including a spacer material, forming a source/drain contact in the trench and removing the spacers and the portion of the ILD with an etching process to form an air-gap, the air-gap disposed under and along sidewalls of the source/drain contact, where the etching process selectively etches the spacer material and the impurity.

Various embodiments of the present application are directed towards a method for forming a metal-insulator-metal (MIM) capacitor comprising an enhanced interfacial layer to reduce breakdown failure. In some embodiments, a bottom electrode layer is deposited over a substrate. A native oxide layer is formed on a top surface of the bottom electrode layer and has a first adhesion strength with the top surface. A plasma treatment process is performed to replace the native oxide layer with an interfacial layer. The interfacial layer is conductive and has a second adhesion strength with the top surface of the bottom electrode layer, and the second adhesion strength is greater than the first adhesion strength. An insulator layer is deposited on the interfacial layer. A top electrode layer is deposited on the insulator layer. The top and bottom electrode layers, the insulator layer, and the interfacial layer are patterned to form a MIM capacitor.

A method of fabricating a semiconductor device includes forming a low-k dielectric layer over a substrate and depositing a cap layer over the low-k dielectric layer. A treatment process is performed to the cap layer. After the treatment process to the cap layer is performed, the low-k dielectric layer is etched to form a plurality of trenches using the cap layer as an etching mask.

A semiconductor device includes: a sidewall insulating film; a gate electrode; source and drain regions; a first stress film; and a second stress film.

The present disclosure provides methods for forming conductive features in a dielectric layer without using adhesion layers or barrier layers and devices formed thereby. In some embodiments, a structure comprising a dielectric layer over a substrate, and a conductive feature disposed through the dielectric layer. The dielectric layer has a lower surface near the substrate and a top surface distal from the substrate. The conductive feature is in direct contact with the dielectric layer, and the dielectric layer comprises an implant species. A concentration of the implant species in the dielectric layer has a peak concentration proximate the top surface of the dielectric layer, and the concentration of the implant species decreases from the peak concentration in a direction towards the lower surface of the dielectric layer.

An integrated circuit device includes a first interconnect layer, and a conductive first interconnect feature and a conductive second interconnect feature laterally separated by a body of insulating or semiconductor material. In an example, the first and second interconnect features are above the first interconnect layer. The integrated circuit device further includes a non-conductive feature above and on the first interconnect feature, and a conductive third interconnect feature above and on the second interconnect feature. The integrated circuit device also includes a second interconnect layer above the non-conductive feature and third interconnect features. In an example, the second and third interconnect features conductively couple the first and second interconnect layers.

The current disclosure describes techniques of protecting a metal interconnect structure from being damaged by subsequent chemical mechanical polishing processes used for forming other metal structures over the metal interconnect structure. The metal interconnect structure is receded to form a recess between the metal interconnect structure and the surrounding dielectric layer. A metal cap structure is formed within the recess. An upper portion of the dielectric layer is strained to include a tensile stress which expands the dielectric layer against the metal cap structure to reduce or eliminate a gap in the interface between the metal cap structure and the dielectric layer.

Methods of etching a metal layer and a metal-containing barrier layer to a predetermined depth are described. In some embodiments, the metal layer and metal-containing barrier layer are formed on a substrate with a first dielectric and a second dielectric thereon. The metal layer and the metal-containing barrier layer formed within a feature in the first dielectric and the second dielectric. In some embodiments, the metal layer and metal-containing barrier layer can be sequentially etched from a feature formed in a dielectric material. In some embodiments, the sidewalls of the feature formed in a dielectric material are passivated to change the adhesion properties of the dielectric material.