Abstract:
A method for fabricating a self-aligned diffusion-barrier cap on a Cu- containing conductive element in an integrated-circuit device comprises: - providing a substrate having a Cu-containing conductive element embedded laterally into a dielectric layer and having an exposed surface; - depositing a metal layer on the exposed surface of conductive element; - inducing diffusion of metal from the metal layer into a top section of the conductive element; - removing the remaining metal layer; - letting diffused metal in the top section of the conductive element and particles of a second constituent react with each other so as to build a compound covering the conductive element. The metal of the metal layer and the second constituent are chosen so that the compound forms a diffusion barrier against Cu diffusion. A reduction the dielectric constant of the dielectric material in an interconnect stack of an integrated-circuit device is achieved.
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 crystalorientations, comprisesselectively incorporating Si into only a first set of crystallites withat least one first crystalorientation, 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. The processing improves the properties of the diffusion-barrier cap and secures a continuous formation of a diffusion-barrier layer on the interconnect element.
Abstract:
The present invention relates to a method for fabricating a semiconductor device. For improving the adhesion between a copper-containing interconnect element and a diffusion barrier on top of it, a first dielectric layer (108) of a first dielectric material is deposited on an exposed surface (102.1) of the interconnect element. Susequently, particles (110) are implanted into the first dielectric layer and the interconnect element (102) so as to let the interconnect material mix with the first dielectric material in a first interface region (102.2) between the interconnect element and thefirst dielectric layer.
Abstract:
An interconnect structure on a substrate is provided. The interconnect structure comprises electrically conductive interconnect elements on at least two interconnect levels on or above a substrate level. In the interconnect structure of the invention, at least one electrically conductive via connects a first interconnect element on one interconnect level or on the substrate level to a second interconnect element on a different interconnect level. The via extends in a via opening of a first dielectric layer and comprises an electrically conductive via material that contains electrically conductive cylindrical carbon nanostructures. At least one cover-layer segment reaches into a lateral extension of the via opening and defines a via aperture that is small enough to prevent a penetration of the carbon nanostructures through the via aperture. This structure enhances control of carbon nanostructure growth in a height direction during fabrication of the interconnect structure.
Abstract:
An interconnect structure on a substrate is provided. The interconnect structure comprises electrically conductive interconnect elements on at least two interconnect levels on or above a substrate level. In the interconnect structure of the invention, at least one electrically conductive via connects a first interconnect element on one interconnect level or on the substrate level to a second interconnect element on a different interconnect level. The via extends in a via opening of a first dielectric layer and comprises an electrically conductive via material that contains electrically conductive cylindrical carbon nanostructures. At least one cover-layer segment reaches into a lateral extension of the via opening and defines a via aperture that is small enough to prevent a penetration of the carbon nanostructures through the via aperture. This structure enhances control of carbon nanostructure growth in a height direction during fabrication of the interconnect structure.
Abstract:
The present invention relates to an integrated-circuit device that has at least one Copper-containing feature in a dielectric layer, and a diffusion-barrier layer stack arranged between the feature and the dielectric layer. The integrated-circuit device of the invention has a diffusion-barrier layer stack, which comprises, in a direction from the Copper-containing feature to the dielectric layer, a CuSiN layer and a SiN layer. This layer combinat ion provides an efficient barrier for suppressing Copper diffusion from the feature into the dielectric layer. Furthermore, a CuSiN/SiN layer sequence provides an improved adhesion between the layers of the diffusion-barrier layer stack and the dielectric layer, and thus improves the electromigration performance of the integrated-circuit device during operation. Therefore, the reliability of device operation and the lifetime of the integrate- circuit device are improved in comparison with prior-art devices. The invention further relates to a method for fabricating such an integrated-circuit device.
Abstract:
The present invention relates to a metal-interconnect structure for electrically connecting integrated-circuit elements in an integrated-circuit device. It solves several problems of operational reliabilit y in damascene interconnect structures, due to corner effects and structural defects present at top edges of interconnect lines fabricated according to prior-art processing technologies. In alternative configurations of the metal interconnect structure, capping spacers (334) are arranged abutting and covering outer top edges (316c) of interconnect lines (304) or lateral barrier liners (316), respectively. The interconnect structure of the invent ion eliminates the negative influence of these critical regio ns in the metal-interconnect structure on the operational reliability of an integrated-circuit device.
Abstract:
The invention concerns a method of forming a metal- insulator-metal capacitor having top and bottom plates separated by a dielectric layer, one of the top and bottom plates having a form comprising at least one protrusion extending into a corresponding cavity in the other of the top and bottom plates, the method including the steps of growing one or more nanofibers on a base surface.
Abstract:
The invention concerns a method of forming a metal- insulator-metal capacitor having top and bottom plates separated by a dielectric layer, one of the top and bottom plates having a form comprising at least one protrusion extending into a corresponding cavity in the other of the top and bottom plates, the method including the steps of growing one or more nanofibers on a base surface.
Abstract:
A method for fabricating a self-aligned diffusion-barrier cap on a Cu- containing conductive element in an integrated-circuit device comprises: - providing a substrate having a Cu-containing conductive element embedded laterally into a dielectric layer and having an exposed surface; - depositing a metal layer on the exposed surface of conductive element; - inducing diffusion of metal from the metal layer into a top section of the conductive element; - removing the remaining metal layer; - letting diffused metal in the top section of the conductive element and particles of a second constituent react with each other so as to build a compound covering the conductive element. The metal of the metal layer and the second constituent are chosen so that the compound forms a diffusion barrier against Cu diffusion. A reduction the dielectric constant of the dielectric material in an interconnect stack of an integrated-circuit device is achieved.