Abstract: Provided are a semiconductor device and a method for manufacturing the same. Since a plug is formed in a portion of a metal interconnection between a first metal contact and a second metal contact, an amount of a metal interconnection coupled to a second metal contact increases. Also, since the first metal contact is formed so that the upper width is narrower than the lower width by using insulation layers having a different etching selectivity when the first metal contact is formed, it is possible to substantially prevent copper ions of the meal interconnection from being migrated or separated according to the flow of a VPP electric field. Consequently, a contact-not-open phenomenon between the first metal contact and the second metal contact may be prevented.

Abstract: The invention provides semiconductor interconnect structures that have improved reliability and technology extendibility. In the present invention, a second metallic capping layer is located on a surface of a first metallic cap layer which is, in turn, located on a surface of the conductive feature embedded within a first dielectric material. Both the first and second metallic capping layers are located beneath an opening, e.g., a via opening, the is present within an overlying second dielectric material. The second metallic capping layer protects the first dielectric capping layer from being removed (either completely or partially) during subsequent processing steps. Interconnect structures including via gouging features as well as non-via gouging features are disclosed. The present invention provides methods of fabricating such semiconductor interconnect structures.

Abstract: Provided is a method for forming a composite barrier layer with superior barrier qualities and superior adhesion properties to both dielectric materials and conductive materials as the composite barrier layer extends throughout the semiconductor device. The composite barrier layer may be formed in regions where it is disposed between two conductive layers and in regions where it is disposed between a conductive layer and a dielectric material. The composite barrier layer may consist of various pluralities of layers and the arrangement of layers that form the composite barrier layer may differ as the barrier layer extends throughout different sections of the device. Amorphous layers of the composite barrier layer generally form boundaries with dielectric materials and crystalline layers generally form boundaries with conductive materials such as interconnect materials.

Abstract: A method includes forming conductive material in a contact hole and a TSV opening, and then performing one step to remove portions of the conductive material outside the contact hole and the TSV opening to leave the conductive material in the contact hole and the TSV opening, thereby forming a contact plug and a TSV structure, respectively. In some embodiments, the removing step is performed by a CMP process.

Abstract: A method for fabricating a semiconductor device includes forming an inter-layer insulation layer on a substrate; forming openings in the inter-layer insulation layer; forming a metal barrier layer in the openings and on the inter-layer insulation layer; forming a first conductive layer on the metal barrier layer and filled in the openings; etching the first conductive layer to form interconnection layers in the openings and to expose portions of the metal barrier layer, the interconnection layers being inside the openings and at a depth from a top of the openings; etching the exposed portions of the metal barrier layer to obtain a sloped profile of the metal barrier layer at top lateral portions of the openings; forming a second conductive layer over the inter-layer insulation layer, the interconnection layers and the metal barrier layer with the sloped profile; and patterning the second conductive layer to form metal lines.

Abstract: The invention provides a method of forming a film stack on a substrate, comprising depositing a tungsten nitride layer on the substrate, subjecting the substrate to a nitridation treatment using active nitrogen species from a remote plasma, and depositing a conductive bulk layer directly on the tungsten nitride layer without depositing a tungsten nucleation layer on the tungsten nitride layer as a growth site for tungsten.

Abstract: An interconnect structure is provided, including a layer of dielectric material having at least one opening and a first barrier layer on sidewalls defining the opening. A ruthenium-containing second barrier layer overlays the first barrier layer, the second barrier layer having a ruthenium zone, a ruthenium oxide zone, and a ruthenium-rich zone. The ruthenium zone is interposed between the first barrier layer and the ruthenium oxide zone. The ruthenium oxide zone is interposed between the ruthenium zone and the ruthenium-rich zone.

Abstract: A semiconductor device includes an interlayer insulating film formed over a semiconductor substrate, a through hole formed in the interlayer insulating film, a Cu film filling the through hole, and a metal-containing base film formed on the sidewall inside the through hole and serving as a base of the Cu film. The metal-containing base film has a metal nitride layer at the interface with the Cu film in a first region including a sidewall area adjacent to the opening of the through hole. In a second region including a sidewall area nearer to the semiconductor substrate than is the first region, the metal-containing base film has a metal layer at the interface with the Cu film. The deposition rate of the Cu film on the surface of the metal layer is greater than the deposition rate of the Cu film on the surface of the metal nitride layer.

Abstract: An improved semiconductor structure consists of interconnects in an upper interconnect level connected to interconnects in a lower interconnect level through use of a conductive protrusion located at the bottom of a via opening in an upper interconnect level, the conductive protrusion extends upward from bottom of the via opening and into the via opening. The improved interconnect structure with the conductive protrusion between the upper and lower interconnects enhances overall interconnect reliability.

Abstract: Manufacturing a damascene structure involves: forming a sacrificial layer (20) on a substrate (10) to protect an area around a recess (30) for the damascene structure, forming a barrier layer (40) in the recess, and in electrical contact with the sacrificial layer, forming the damascene structure (50) in the recess, and planarizing. During the planarizing the sacrificial layer reacts electrochemically with the barrier layer or with the damascene structure. This can alter a relative rate of removal of the damascene structure and the sacrificial layer so as to reduce dishing or protrusion of the damascene structure, and reduce copper residues, and reduce barrier corrosion. The barrier layer can be formed by ALCVD. The barrier material being one or more of WCN and TaN. The sacrificial layer can be TaN, TiN or W.

Abstract: A semiconductor contact structure includes a copper plug formed within a dual damascene, single damascene or other opening formed in a dielectric material and includes a composite barrier layer between the copper plug and the sidewalls and bottom of the opening. The composite barrier layer preferably includes an ALD TaN layer disposed on the bottom and along the sides of the opening although other suitable ALD layers may be used. A barrier material is disposed between the copper plug and the ALD layer. The barrier layer may be a Mn-based barrier layer, a Cr-based barrier layer, a V-based barrier layer, a Nb-based barrier layer, a Ti-based barrier layer, or other suitable barrier layers.

Abstract: Cobalt is added to a copper seed layer, a copper plating layer, or a copper capping layer in order to modify the microstructure of copper lines and vias. The cobalt can be in the form of a copper-cobalt alloy or as a very thin cobalt layer. The grain boundaries configured in bamboo microstructure in the inventive metal interconnect structure shut down copper grain boundary diffusion. The composition of the metal interconnect structure after grain growth contains from about 1 ppm to about 10% of cobalt in atomic concentration. Grain boundaries extend from a top surface of a copper-cobalt alloy line to a bottom surface of the copper-cobalt alloy line, and are separated from any other grain boundary by a distance greater than a width of the copper-cobalt alloy line.

Abstract: A seed layer is formed on a surface of an insulating film and along a recess of the insulating film, and after a copper wiring is buried in the recess, a barrier film is formed, and an excessive metal is removed from the wiring. On a surface of a copper lower layer conductive path exposed at the bottom of the recess, a natural oxide of the copper is reduced or removed. On a substrate from which the natural oxide is reduced or removed, the seed layer, composed of a self-forming barrier metal having oxidative tendency higher than that of copper or an alloy of such metal and copper, is formed. The substrate is heated after burying copper in the recess. Thus, a barrier layer is formed by oxidizing the self-forming barrier metal. An excessive portion of the self-forming barrier metal is deposited on a surface of the buried copper.

Abstract: Embodiments of the present invention pertain to the formation of microelectronic structures. Low k dielectric materials need to exhibit a dielectric constant of less than about 2.6 for the next technology node of 32 nm. The present invention enables the formation of semiconductor devices which make use of such low k dielectric materials while providing an improved flexural and shear strength integrity of the microelectronic structure as a whole.

Abstract: A multilayered wiring is formed in a prescribed area in an insulating film that is formed on a semiconductor substrate. Dual damascene wiring that is positioned on at least one layer of the multilayered wiring is composed of an alloy having copper as a principal component. The concentration of at least one metallic element contained in the alloy as an added component in vias of the dual damascene wiring is determined according to the differences in the width of the wiring of an upper layer where the vias are connected. Specifically, a larger wiring width in the upper layer corresponds to a higher concentration of at least one metallic element within the connected vias. Accordingly, increases in the resistance of the wiring are minimized, the incidence of stress-induced voids is reduced, and reliability can be improved.

Abstract: A semiconductor device manufacturing method includes forming an interlayer dielectric film above a semiconductor substrate; forming a first wiring trench with a first width and a second wiring trench with a second width that is larger than the first width inr the interlayer dielectric film; forming a first seed layer that includes a first additional element in the first wiring trench and the second wiring trench; forming a first copper layer over the first seed layer; removing the first copper layer and the first seed layer in the second wiring trench while leaving the first copper layer and the first seed layer in the first wiring trench; forming a second seed layer in the second wiring trench after removing the first copper layer and the first seed layer in the second wiring trench; and forming a second copper layer over the second seed layer.

Abstract: A method is disclosed for metallizing a substrate comprising an interconnect feature in the manufacture of a microelectronic device, wherein the interconnect feature comprises a bottom, a sidewall, and a top opening having a diameter, D. The method comprises the following steps: depositing a barrier layer on the bottom and the sidewall of the interconnect feature, the barrier layer comprising a metal selected from the group consisting of ruthenium, tungsten, tantalum, titanium, iridium, rhodium, and combinations thereof; contacting the substrate comprising the interconnect feature comprising the bottom and sidewall having the barrier layer thereon with an aqueous composition comprising a reducing agent and a surfactant; and depositing copper metal onto the bottom and the sidewall of the interconnect feature having the barrier layer thereon.

Abstract: Methods of forming field effect transistors include forming a metal alloy gate electrode (e.g., aluminum alloy) containing about 0.5 to about 1.0 atomic percent silicon, on a substrate, and electroless plating an electrically conductive gate protection layer directly on at least a portion of an upper surface of the metal alloy gate electrode. A gate dielectric layer may be formed on the substrate. This gate dielectric layer may have a dielectric constant greater than a dielectric constant of silicon dioxide. The forming of the metal alloy gate electrode may include forming a metal alloy gate electrode directly on an upper surface of the gate dielectric layer.

Abstract: According to an embodiment of the invention, a chip package is provided, which includes: a substrate having an upper surface and a lower surface; a hole extending from the upper surface toward the lower surface; an insulating layer located overlying a sidewall of the hole; and a material layer located overlying the sidewall of the hole, wherein the material layer is separated from the upper surface of the substrate by a distance and a thickness of the material layer decreases along a direction toward the lower surface.

Abstract: A programmable resistance, chalcogenide, switching or phase-change material device includes a substrate with a plurality of stacked layers including a conducting bottom electrode layer, an insulative layer having an opening formed therein, an active material layer deposited over both the insulative layer, within the opening, and over selected portions of the bottom electrode, and a top electrode layer deposited over the active material layer. The device uses temperature and pressure control methods to increase surface mobility in an active material layer, thus providing complete coverage or fill of the openings in the insulative layer, selected exposed portions of the bottom electrode layer, and the insulative layer.

Abstract: An integrated circuit contact system is provided including forming a contact plug in a dielectric and forming a first barrier layer in a trench in the dielectric and on the contact plug. Further, the system includes removing a portion of the first barrier layer from the bottom of the first barrier layer and depositing the portion of the first barrier layer on the sidewall of the first barrier layer, and forming a second barrier layer over the first barrier layer and filling a corner area of the trench.

Abstract: A method for creating a dual damascene structure while using only one lithography and masking step. Conventional dual damascene structures utilize two lithography steps: one to mask and expose the via, and a second step to mask and expose the trench interconnection. The novel method for creating a dual damascene structure allows for a smaller number of processing steps, thus reducing the processing time needed to complete the dual damascene structure. In addition, a lower number of masks may be needed. The exemplary mask or reticle used within the process incorporates different regions possessing different transmission rates. During the exposing step, light from an exposing source passes through the mask to expose a portion of the photoresist layer on top of the wafer.

Abstract: The present invention relates to a method for fabricating a diffusion-barrier cap on a Cu-containing interconnect element that has crystallites of at least two different crystal orientations, comprises selectively incorporating Si into only a first set of crystallites with at least one first crystal orientation, employing first process conditions, and subsequently selectively forming a first adhesion-layer portion comprising CuSi and a first diffusion-barrier-layer portion only on the first set of crystallites, thus forming a first barrier-cap portion, and subsequently selectively incorporating Si into only the second set of crystallites, employing second process conditions that differ from the first process conditions, and forming a second barrier-cap portion comprising a Si-containing second diffusion-barrier layer portion on the second set of crystallites of the interconnect element.

Abstract: Embodiments of the invention generally provide methods for depositing and compositions of tantalum carbide nitride materials. The methods include deposition processes that form predetermined compositions of the tantalum carbide nitride material by controlling the deposition temperature and the flow rate of a nitrogen-containing gas during a vapor deposition process, including thermal decomposition, CVD, pulsed-CVD, or ALD. In one embodiment, a method for forming a tantalum-containing material on a substrate is provided which includes heating the substrate to a temperature within a process chamber, and exposing the substrate to a nitrogen-containing gas and a process gas containing a tantalum precursor gas while depositing a tantalum carbide nitride material on the substrate.

Abstract: A metal line of a semiconductor device includes an insulation layer formed on a semiconductor substrate. The insulation layer has a metal line forming region. A diffusion barrier is formed on a surface of the metal line forming region of the insulation layer. The diffusion barrier includes a stack structure including an MoxSiyNz layer and an Mo layer. A metal layer is formed on the diffusion barrier to fill the metal line forming region of the insulation layer.

Abstract: A semiconductor device includes: a semiconductor substrate in which an integrated circuit is formed; an interconnect layer which includes a linear section and a land section connected with the linear section; and an underlayer disposed under the interconnect layer, and the land section includes a first section which is in contact with the underlayer, and a second section which is not in contact with the underlayer.

Abstract: Thin films are formed by formed by atomic layer deposition, whereby the composition of the film can be varied from monolayer to monolayer during cycles including alternating pulses of self-limiting chemistries. In the illustrated embodiments, varying amounts of impurity sources are introduced during the cyclical process. A graded gate dielectric is thereby provided, even for extremely thin layers. The gate dielectric as thin as 2 nm can be varied from pure silicon oxide to oxynitride to silicon nitride. Similarly, the gate dielectric can be varied from aluminum oxide to mixtures of aluminum oxide and a higher dielectric material (e.g., ZrO2) to pure high k material and back to aluminum oxide. In another embodiment, metal nitride (e.g., WN) is first formed as a barrier for lining dual damascene trenches and vias. During the alternating deposition process, copper can be introduced, e.g.

Abstract: An integrated circuit structure having improved resistivity and a method for forming the same are provided. The integrated circuit structure includes a dielectric layer, an opening in the dielectric layer, an oxide-based barrier layer directly on sidewalls of the opening, and conductive materials filling the remaining portion of the opening.

Abstract: A metal line in a semiconductor device includes an insulation layer formed on a semiconductor substrate. A metal line forming region is formed in the insulation layer. A metal line is formed to fill the metal line forming region of the insulation layer. And a diffusion barrier that includes an amorphous TaBN layer is formed between the metal line and the insulation layer. The amorphous TaBN layer prevents a copper component from diffusing into the semiconductor substrate, thereby improving upon the characteristics and the reliability of a device.

Abstract: Aspects of the invention include methods for depositing silicon on a substrate. In certain embodiments, the methods include exposing a substrate containing silicon to a halogenated silane in a manner sufficient to deposit the silicon on the substrate. In certain embodiments, the method includes providing a substrate, one or more sources of gas, and a reaction vessel that is in fluid communication with the substrate and the one or more sources of gas. In certain embodiments, the substrate is a low or metallurgical grade silicon which may be subjected to a purification process. In certain embodiments, the reaction vessel is a particle bed reaction vessel that includes a moving bed, such as a fluidized bed which contains silicon and the gas includes a halide.

Abstract: A semiconductor wafer may include, but is not limited to, the following elements. A semiconductor substrate has a device region and a dicing region. A stack of inter-layer insulators may extend over the device region and the dicing region. Multi-level interconnections may be disposed in the stack of inter-layer insulators. The multi-level interconnections may extend in the device region. An electrode layer may be disposed over the stack of inter-layer insulators. The electrode layer may extend in the device region. The electrode layer may cover the multi-level interconnections. A cracking stopper groove may be disposed in the dicing region. The cracking stopper groove may be positioned outside the device region.

Abstract: A method for manufacturing a semiconductor device includes providing a substrate including pattern formed over the substrate and a first insulating layer formed over the pattern. A diffusion barrier layer is formed over the first insulation layer. A second insulating layer is formed over the diffusion barrier layer. The second insulating layer, the diffusion layer, and the first insulating layer are patterned to form a trench exposing the pattern. A metal layer is formed over the second insulating layer and within the trench to define a metal interconnection pattern coupling the pattern within the trench, the metal particles from the metal layer diffuse into the second insulating layer. The second insulation layer and the metal particles that have been diffused therein are removed.

Abstract: A method for plating copper onto a semiconductor integrated circuit device substrate by forming an initial metal deposit in the feature which has a profile comprising metal on the bottom of the feature and a segment of the sidewalls having essentially no metal thereon, electrolessly depositing copper onto the initial metal deposit to fill the feature with copper. A method for plating copper onto a semiconductor integrated circuit device substrate by forming a deposit comprising a copper wettable metal in the feature, forming a copper-based deposit on the top-field surface, and depositing copper onto the deposit comprising the copper wettable metal to fill the feature with copper.

Abstract: Processes for minimizing contact resistance when using nickel silicide (NiSi) and other similar contact materials are described. These processes include optimizing silicide surface cleaning, silicide surface passivation against oxidation and techniques for diffusion barrier/catalyst layer deposition. Additionally, processes for generating a noble metal (for example platinum, iridium, rhenium, ruthenium, and alloys thereof) activation layer that enables the electroless barrier layer deposition on a NiSi-based contact material are described. The processes may be employed when using NiSi-based materials in other end products. The processes may be employed on silicon-based materials.

Abstract: A semiconductor interconnect structure and method providing an embedded barrier layer to prevent damage to the dielectric material during or after Chemical Mechanical Polishing. The method employs a combination of an embedded film, etchback, using either selective CoWP or a conformal cap such as a SiCNH film, to protect the dielectric material from the CMP process as well as subsequent etch, clean and deposition steps of the next interconnect level.

Abstract: Manufacturing a damascene structure involves: forming a sacrificial layer (20) on a substrate (10) to protect an area around a recess (30) for the damascene structure, forming a barrier layer (40) in the recess, and in electrical contact with the sacrificial layer, forming the damascene structure (50) in the recess, and planarising. During the planarising the sacrificial layer reacts electrochemically with the barrier layer or with the damascene structure. This can alter a relative rate of removal of the damascene structure and the sacrificial layer so as to reduce dishing or protrusion of the damascene structure, and reduce copper residues, and reduce barrier corrosion. The barrier layer can be formed by ALCVD. The barrier material being one or more of WCN and TaN. The sacrificial layer can be TaN, TiN or W.

Abstract: In one exemplary embodiment, a method of manufacturing a semiconductor device is disclosed in which a damascene interconnect is formed above an underlying insulating film. The method includes forming an interconnect insulating film above the underlying insulating film such that a film density of the interconnect insulating film is relatively greater at a lower side thereof and relatively less at an upper side thereof. The interconnect insulating film is anisotropically dry etched to form an interconnect trench. The interconnect trench is wet etched such that an upper portion of a vertical cross section thereof exhibits a positive taper. A barrier metal film is formed along an inner surface of the interconnect trench including the positive taper. Further, the interconnect trench is filled with an interconnect conductor by plating over the barrier metal film.

Abstract: An interconnect structure including a gouging feature at the bottom of a via opening and a method of forming the same are provided. The method of the present invention does not disrupt the coverage of the deposited trench diffusion barrier in a line opening that is located atop the via opening, and/or does not introduce damages caused by creating a gouging feature at the bottom of the via opening by sputtering into the interconnect dielectric material that includes the via and line openings. Such an interconnect structure is achieved by providing a gouging feature in the bottom of the via opening by first forming the line opening within the interconnect dielectric, followed by forming the via opening and then the gouging feature.

Abstract: A method of forming a semiconductor structure includes providing a substrate; forming a low-k dielectric layer over the substrate; embedding a conductive wiring into the low-k dielectric layer; and thermal soaking the conductive wiring in a carbon-containing silane-based chemical to form a barrier layer on the conductive wiring. A lining barrier layer is formed in the opening for embedding the conductive wiring. The lining barrier layer may comprise same materials as the barrier layer, and the lining barrier layer may be recessed before forming the barrier layer and may contain a metal that can be silicided.

Abstract: Improved high aspect ratio vias and techniques for the formation thereof are provided. In one aspect, a method of fabricating a copper plated high aspect ratio via is provided. The method comprises the following steps. A high aspect ratio via is etched in a dielectric layer. A diffusion barrier layer is deposited into the high aspect ratio via and over one or more surfaces of the dielectric layer. A copper layer is deposited over the diffusion barrier layer. A ruthenium layer is deposited over the copper layer. The high aspect ratio via is filled with copper plated onto the ruthenium layer. A copper plated high aspect ratio via formed by this method is also provided.

Abstract: The present invention is a method of film deposition that comprises a film-depositing step of supplying a high-melting-point organometallic material gas and a nitrogen-containing gas to a processing vessel that can be evacuated, so as to deposit a thin film of a metallic compound of a high-melting-point metal on a surface of an object to be processed placed in the processing vessel. A partial pressure of the nitrogen-containing gas during the film-depositing step is 17% or lower, in order to increase carbon density contained in the thin film.

Abstract: A structure and methods of fabricating the structure. The structure comprising: a trench in a dielectric layer; an electrically conductive liner, an electrically conductive core conductor and an electrically conductive fill material filling voids between said liner and said core conductor.

Abstract: Disclosed are embodiments of an improved high aspect ratio electroplated metal structure (e.g., a copper or copper alloy interconnect, such as a back end of the line (BEOL) or middle of the line (MOL) contact) in which the electroplated metal fill material is free from seams and/or voids. Also, disclosed are embodiments of a method of forming such an electroplated metal structure by lining a high aspect ratio opening (e.g., a high aspect ratio via or trench) with a metal-plating seed layer and, then, forming a protective layer over the portion of the metal-plating seed layer adjacent to the opening sidewalls so that subsequent electroplating occurs only from the bottom surface of the opening up.

Abstract: A method of forming a diffusion barrier for use in semiconductor device manufacturing includes depositing, by a physical vapor deposition (PVD) process, an iridium doped, tantalum based barrier layer over a patterned interlevel dielectric (ILD) layer, wherein the barrier layer is deposited with an iridium concentration of at least 60 atomic % such that the barrier layer has a resulting amorphous structure.

Abstract: A semiconductor device includes a semiconductor substrate, a copper-containing metal interconnect over the semiconductor substrate, and a copper-containing connection plug, and the metal interconnect includes metal elements other than copper, and a concentration of different metal elements in a connection portion between the metal interconnect and the connection plug is higher than a concentration of the different metal elements in a center portion of the metal interconnect, and higher than a concentration of different elements in upper face portion of the metal interconnect other than the connection portion.

Abstract: A method is described in which a contact hole to an interconnect in an insulating layer is fabricated. A barrier layer is subsequently applied. Afterward, a photoresist layer is applied, irradiated and developed. With the aid of a galvanic method, a copper contact is then produced in the contact hole. Either the barrier layer or an additional boundary electrode layer serves as a boundary electrode in the galvanic process. Critical metal contaminations are minimized in production.

Abstract: A damascene process is described using a copper fill process to fill a trench (12). The copper fill (20) is started with a deposited seed layer which includes (5) copper and titanium. Some titanium migrates to the surface during the copper fill process. The structure is annealed in a nitrogen atmosphere which creates a self-aligned TiN barrier (24) at the surface of the copper fill (20). Air gaps (26) may be created in the same annealing process. The process may be used to form a multilayer structure.

Abstract: Method of manufacturing a structure which includes the steps of providing a structure having an insulator layer with at least one interconnect, forming a sub lithographic template mask over the insulator layer, and selectively etching the insulator layer through the sub lithographic template mask to form sub lithographic features spanning to a sidewall of the plurality of interconnects.

Abstract: Provided is a Cu electrical interconnection film forming method, wherein an adhesive layer (base film) having improved adhesiveness with a Cu electrical interconnection film is used, in a semiconductor device manufacturing process. After forming a barrier film on a substrate whereupon a hole or the like is formed, a PVD-Co film or a CVD-Co film or an ALD-Co film is formed on the barrier film. Then, after filling up or burying the hole or the like, which has the Co film formed on the surface, with a CVD-Cu film or a PVD-Cu film, heat treatment is performed at a temperature of 350° C. or below, and the Cu electrical interconnection film is formed.

Abstract: A method and apparatus for generating air gaps in a dielectric material of an interconnect structure. One embodiment provides a method for forming a semiconductor structure comprising depositing a first dielectric layer on a substrate, forming trenches in the first dielectric layer, filling the trenches with a conductive material, planarizing the conductive material to expose the first dielectric layer, depositing a dielectric barrier film on the conductive material and exposed first dielectric layer, depositing a hard mask layer over the dielectric barrier film, forming a pattern in the dielectric barrier film and the hard mask layer to expose selected regions of the substrate, oxidizing at least a portion of the first dielectric layer in the selected region of the substrate, removing oxidized portion of the first dielectric layer to form reversed trenches around the conductive material, and forming air gaps in the reversed trenches while depositing a second dielectric material in the reversed trenches.