Methods of forming decoupling capacitors in interconnect structures formed on backsides of semiconductor devices and semiconductor devices including the same are disclosed. In an embodiment, a device includes a device layer including a first transistor; a first interconnect structure on a front-side of the device layer; a second interconnect structure on a backside of the device layer, the second interconnect structure including a first dielectric layer on the backside of the device layer; a contact extending through the first dielectric layer to a source/drain region of the first transistor; a first conductive layer including a first conductive line electrically connected to the source/drain region of the first transistor through the contact; and a second dielectric layer adjacent the first conductive line, the second dielectric layer including a material having a k-value greater than 7.0, a first decoupling capacitor including the first conductive line and the second dielectric layer.

A method of forming a semiconductor device having a vertical metal line interconnect (via) fully aligned to a first direction of a first interconnect layer and a second direction of a second interconnect layer in a selective recess region by forming a plurality of metal lines in a first dielectric layer; and recessing in a recess region first portions of the plurality of metal lines such that top surfaces of the first portions of the plurality of metal lines are below a top surface of the first dielectric layer; wherein a non-recess region includes second portions of the plurality of metal lines that are outside the recess region.

A manufacturing method of a semiconductor structure includes the following steps. A substrate is provided. A barrier layer is formed on the substrate. A sacrificial layer is formed on the barrier layer. An opening pattern is formed over the sacrificial layer by utilizing a photolithography process. The sacrificial layer is etched according to the opening pattern to form first trenches by using the barrier layer as an etch stop layer. A medium layer material is filled in the first trenches. The sacrificial layer is etched to form second trenches by using the barrier layer as the etch stop layer. A hard mask layer material is filled in the second trenches. The medium layer material is etched to form a hard mask layer by using the barrier layer as the etch stop layer.

A semiconductor interconnect structure includes a conductive line electrically coupled to an active semiconductor device, a first etch stop layer formed over the conductive line, a first dielectric layer formed over the first etch stop layer, a second etch stop layer formed over the first dielectric layer, a second dielectric layer formed over the second etch stop layer, and an interconnect structure electrically coupled to the via and extending through the first etch stop layer, the first dielectric layer, the second etch stop layer, and the second dielectric layer. The interconnect structure includes a via extending through the first etch stop layer, the second etch stop layer, and the first dielectric layer and a trench extending through the second dielectric layer.

In certain embodiments, a method includes forming a first etch stop layer on a first metallization layer of a semiconductor substrate. The method further includes forming, prior to forming a second metallization layer over the first metallization layer, an opening in the first etch stop layer according to a supervia mask. The method further includes forming the second metallization layer over the first metallization layer and forming a second etch stop layer on the second metallization layer. The method further includes forming, prior to forming a third metallization layer over the second metallization layer, an opening in the second etch stop layer according to the supervia mask. The method further includes forming the third metallization layer over the second metallization layer and etching a supervia opening from the third metallization layer to the first metallization layer according to the supervia mask.

A semiconductor structure includes a conductive feature, a first metal-based etch-stop layer over the underlying structure, a metal-free etch-stop layer over the first metal-based etch-stop layer, a second metal-based etch-stop layer over the metal-free etch-stop layer, an interlayer dielectric layer over the second metal-based etch-stop layer, and an interconnect structure extending through the first metal-based etch-stop layer, metal-free etch-stop layer, and the second metal-based etch-stop layer, wherein a bottom portion of the conductive interconnect structure directly contacts the conductive feature. The first metal-based etch-stop layer may include a first metallic component having one of aluminum, tantalum, titanium, or hafnium, and the second metal-based etch-stop layer may include a second metallic component the same as or different from the first metallic component. The first metal-based etch-stop layer and the second metal-based etch-stop layer may both be free of silicon.

A method for forming an interconnection structure for a semiconductor device is provided. The method includes: (i) forming a conductive layer on an insulating layer; (ii) forming above the conductive layer a first set of mandrel lines of a first material; (iii) forming a set of spacer lines of a second material different from the first material, wherein the spacer lines of the second material are formed on sidewalls of the first set of mandrel lines; (iv) forming a second set of mandrel lines of a third material different from the first and second materials, wherein the second set of mandrel lines fill gaps between spacer lines of the set of spacer lines; (v) cutting at least a first mandrel line of the second set of mandrel lines into two line segments separated by a gap by etching said first mandrel line of the second set of mandrel lines selectively to the set of spacer lines and the first set of mandrel lines, cutting at least a first mandrel line of the first set of mandrel lines into two line segments separated by a gap by etching said first mandrel line of the first set of mandrel lines selectively to the set of spacer lines and the second set of mandrel lines; (vi) removing the set of spacer lines, selectively to the first and second sets of mandrel lines, thereby forming an alternating pattern of mandrel lines of the first set of mandrel lines and mandrel lines of the second set of mandrel lines; and (vii) patterning the conductive layer to form a set of conductive lines, wherein the patterning comprises etching while using the alternating pattern of mandrel lines of the first and second sets of mandrel lines as an etch mask.

A device comprises a first metal structure, a dielectric structure, a dielectric residue, and a second metal structure. The dielectric structure is over the first metal structure. The dielectric structure has a stepped sidewall structure. The stepped sidewall structure comprises a lower sidewall and an upper sidewall laterally set back from the lower sidewall. The dielectric residue is embedded in a recessed region in the lower sidewall of the stepped sidewall structure of the dielectric structure. The second metal structure extends through the dielectric structure to the first metal structure.

A method of forming an integrated circuit includes: forming a dielectric layer, a hard mask layer, a film layer and a photoresist layer; and patterning the photoresist layer to form a via mask, where the via mask is oversized, such that the via mask extends across opposing sides of a metal line mask in the hard mask layer. The method further includes: etching the film layer and the dielectric layer based on the patterned photoresist layer; ashing the photoresist layer and the film layer; etching the dielectric layer based on a pattern of the hard mask layer to provide a via region and a metal line region; etching the hard mask layer and the dielectric layer; and performing a plurality of dual damascene process operations to form a via in the via region and a metal line in the metal line region in the integrated circuit.

A semiconductor device is provided. The semiconductor device includes a first wiring and a second wiring disposed at a first metal level, a third wiring and a fourth wiring disposed at a second metal level different from the first metal level, a first via which directly connects the first wiring and the third wiring, a fifth wiring disposed at a third metal level between the first metal level and the second metal level and connected to the second wiring, and a second via which directly connects the fourth wiring and the fifth wiring.