Abstract: Methods of forming copper interconnects free from via-to-via leakage currents and having low resistances are disclosed. In a first aspect, a barrier layer is deposited on the first metal layer prior to copper oxide sputter-etching to prevent copper atoms from reaching the interlayer dielectric and forming via-to-via leakage current paths therein. In a second aspect, a capping dielectric barrier layer is deposited over the first metal layer prior to sputter etching. During sputter-etching, the capping dielectric barrier layer redistributes on the sidewalls of the interlayer dielectric, preventing sputter-etched copper atoms from reaching the interlayer dielectric and forming via-to-via leakage paths therein. In a third aspect, both a capping dielectric barrier layer and a barrier layer are deposited over the first metal layer prior to sputter-etching to prevent copper atoms produced during sputter-etching from reaching the interlayer dielectric and forming via-to-via leakage paths therein.

Abstract: Methods of forming copper interconnects free from via-to-via leakage currents and having low resistances are disclosed. In a first aspect, a barrier layer is deposited on the first metal layer prior to copper oxide sputter-etching to prevent copper atoms from reaching the interlayer dielectric and forming via-to-via leakage current paths therein. In a second aspect, a capping dielectric barrier layer is deposited over the first metal layer prior to sputter etching. During sputter-etching, the capping dielectric barrier layer redistributes on the sidewalls of the interlayer dielectric, preventing sputter-etched copper atoms from reaching the interlayer dielectric and forming via-to-via leakage paths therein. In a third aspect, both a capping dielectric barrier layer and a barrier layer are deposited over the first metal layer prior to sputter-etching to prevent copper atoms produced during sputter-etching from reaching the interlayer dielectric and forming via-to-via leakage paths therein.

Abstract: A method and apparatus for Metallization process sequences are provided for forming reliable interconnects including lines, vias and contacts. An initial barrier layer, such as Ta or TaN, is first formed on a patterned substrate followed by seed layer formed using high density plasma PVD techniques. The structure is then filled using either 1) electroplating, 2) PVD reflow, 3) CVD followed by PVD reflow, or 4) CVD.

Abstract: Metallization process sequences are provided for forming reliable interconnects including lines, vias and contacts. An initial barrier layer, such as Ta or TaN, is first formed on a patterned substrate followed by seed layer formed using high density plasma PVD techniques. The structure is then filled using either 1) electroplating, 2) PVD reflow, 3) CVD followed by PVD reflow, or 4) CVD.

Abstract: Methods of forming copper interconnects free from via-to-via leakage currents and having low resistances are disclosed. In a first aspect, a barrier layer is deposited on the first metal layer prior to copper oxide sputter-etching to prevent copper atoms from reaching the interlayer dielectric and forming via-to-via leakage current paths therein. In a second aspect, a capping dielectric barrier layer is deposited over the first metal layer prior to sputter etching. During sputter-etching, the capping dielectric barrier layer redistributes on the sidewalls of the interlayer dielectric, preventing sputter-etched copper atoms from reaching the interlayer dielectric and forming via-to-via leakage paths therein. In a third aspect, both a capping dielectric barrier layer and a barrier layer are deposited over the first metal layer prior to sputter-etching to prevent copper atoms produced during sputter-etching from reaching the interlayer dielectric and forming via-to-via leakage paths therein.

Abstract: One aspect of the invention provides a consistent metal electroplating technique to form void-less metal interconnects in sub-micron high aspect ratio features on semiconductor substrates. One embodiment of the invention provides a method for filling sub-micron features on a substrate, comprising reactive precleaning the substrate, depositing a barrier layer on the substrate using high density plasma physical vapor deposition; depositing a seed layer over the barrier layer using high density plasma physical vapor deposition; and electro-chemically depositing a metal using a highly resistive electrolyte and applying a first current density during a first deposition period followed by a second current density during a second period.

Abstract: We have discovered a method of improving step coverage of a copper seed layer deposited over a semiconductor feature surface which is particularly useful for small size features having a high aspect ratio. We have demonstrated that it is possible to increase the copper seed layer coverage simultaneously at the bottom of a high aspect ratio contact via and on the walls of the via by increasing the percentage of the depositing copper species which are ions. The percentage of species ionization which is necessary to obtain sufficient step coverage for the copper seed layer is a function of the aspect ratio of the feature. An increase in the percentage of copper species which are ionized can be achieved using techniques known in the art, including but not limited to applicants' preferred technique, an inductively coupled RF ion metal plasma.

Abstract: Methods of forming copper interconnects free from via-to-via leakage currents and having low resistances are disclosed. In a first aspect, a barrier layer is deposited on the first metal layer prior to copper oxide sputter-etching to prevent copper atoms from reaching the interlayer dielectric and forming via-to-via leakage current paths therein. In a second aspect, a capping dielectric barrier layer is deposited over the first metal layer prior to sputter etching. During sputter-etching, the capping dielectric barrier layer redistributes on the sidewalls of the interlayer dielectric, preventing sputter-etched copper atoms from reaching the interlayer dielectric and forming via-to-via leakage paths therein. In a third aspect, both a capping dielectric barrier layer and a barrier layer are deposited over the first metal layer prior to sputter-etching to prevent copper atoms produced during sputter-etching from reaching the interlayer dielectric and forming via-to-via leakage paths therein.

Abstract: One aspect of the invention provides a consistent metal electroplating technique to form void-less metal interconnects in sub-micron high aspect ratio features on semiconductor substrates. One embodiment of the invention provides a method for filling sub-micron features on a substrate, comprising reactive precleaning the substrate, depositing a barrier layer on the substrate using high density plasma physical vapor deposition; depositing a seed layer over the barrier layer using high density plasma physical vapor deposition; and electro-chemically depositing a metal using a highly resistive electrolyte and applying a first current density during a first deposition period followed by a second current density during a second period.

Abstract: We have discovered a method of improving step coverage of a copper seed layer deposited over a semiconductor feature surface which is particularly useful for small size features having a high aspect ratio. Using a contact via as an example of a high aspect ratio feature, we have demonstrated that despite previously-held views, it is possible to increase the copper seed layer coverage simultaneously at the bottom of the via and on the wall of the via by increasing the percentage of the depositing copper species which are ions. The percentage of species ionization which is necessary to obtain sufficient step coverage for the copper seed layer is a function of the aspect ratio of the feature. For features having a 0.25 &mgr;m or smaller feature size, an aspect ratio of about 3:1 requires that about 50% or more of the copper species be ions at the time of deposition on the substrate.

Abstract: A method of improving step coverage of a copper seed layer deposited over a semiconductor feature surface which is particularly useful for small size features having a high aspect ratio. Using a contact via as an example of a high aspect ratio feature, we have demonstrated that it is possible to increase the copper seed layer coverage simultaneously at both the bottom of the via and on the wall of the via . This increase is achieved by increasing the percentage of the depositing copper species which are ions. The percentage of species ionization which is necessary to obtain sufficient step coverage for the copper seed layer is a function of the aspect ratio of the feature. For features having a 0.25 &mgr;m or smaller feature size, an aspect ratio of about 3:1 requires that about 50% or more of the copper species be ions at the time of deposition on the substrate.

Abstract: A copper metallization structure and its method of formation in which a layer of a copper alloy, such as Cu—Mg or Cu—Al is deposited over a silicon oxide based dielectric layer and a substantially pure copper layer is deposited over the copper alloy layer. The copper alloy layer serves as a seed or wetting layer for subsequent filling of via holes and trenches with substantially pure copper. Preferably, the copper alloy is deposited cold in a sputter process, but, during the deposition of the pure copper layer or afterwards in a separate annealing step, the temperature is raised sufficiently high to cause the alloying element of the copper alloy to migrate to the dielectric layer and form a barrier there against diffusion of copper into and through the dielectric layer. This barrier also promotes adhesion of the alloy layer to the dielectric layer, thereby forming a superior wetting and seed layer for subsequent copper full-fill techniques.

Abstract: Methods of forming copper interconnects free from via-to-via leakage currents and having low resistances are disclosed. In a first aspect, a barrier layer is deposited on the first metal layer prior to copper oxide sputter-etching to prevent copper atoms from reaching the interlayer dielectric and forming via-to-via leakage current paths therein. In a second aspect, a capping dielectric barrier layer is deposited over the first metal layer prior to sputter etching. During sputter-etching, the capping dielectric barrier layer redistributes on the sidewalls of the interlayer dielectric, preventing sputter-etched copper atoms from reaching the interlayer dielectric and forming via-to-via leakage paths therein. In a third aspect, both a capping dielectric barrier layer and a barrier layer are deposited over the first metal layer prior to sputter-etching to prevent copper atoms produced during sputter-etching from reaching the interlayer dielectric and forming via-to-via leakage paths therein.

Abstract: We have discovered that complete copper filling of semiconductor features such as trenches and vias, without the formation of trapped voids, can be accomplished using a copper reflow process when the unfilled portion of the feature structure prior to reflow comprises a capillary within the feature, wherein the volume of the capillary represents between about 20% and about 90%, preferably between about 20% and about 75% of the original feature volume prior to filling with copper. The aspect ratio of the capillary is preferably at least 1.5. The maximum opening dimension of the capillary is less than about 0.8 &mgr;m. The preferred substrate temperature during the reflow process includes either a soak at an individual temperature or a temperature ramp-up or ramp-down where the substrate experiences a temperature within a range from about 300° C. to about 600° C., more preferably between about 300° C. and about 450° C.

Abstract: A copper metallization structure and its method of formation in which a layer of a copper alloy, such as Cu—Mg or Cu—Al is deposited over a silicon oxide based dielectric layer and a substantially pure copper layer is deposited over the copper alloy layer. The copper alloy layer serves as a seed or wetting layer for subsequent filling of via holes and trenches with substantially pure copper. Preferably, the copper alloy is deposited cold in a sputter process, but, during the deposition of the pure copper layer or afterwards in a separate annealing step, the temperature is raised sufficiently high to cause the alloying element of the copper alloy to migrate to the dielectric layer and form a barrier there against diffusion of copper into and through the dielectric layer. This barrier also promotes adhesion of the alloy layer to the dielectric layer, thereby forming a superior wetting and seed layer for subsequent copper full-fill techniques.

Abstract: The barrier effectiveness of a barrier material with respect to a conductive material is evaluated by providing a silicon substrate and then etching said silicon substrate to define an opening therein. The barrier material is then deposited in the opening, followed by a deposition of the conductive material. The silicon substrate is then heated at a predetermined temperature, and reactions between the conductive material and the silicon substrate are detected using a SEM or an optical microscope.

Abstract: Methods of forming copper interconnects free from via-to-via leakage currents and having low resistances are disclosed. In a first aspect, a barrier layer is deposited on the first metal layer prior to copper oxide sputter-etching to prevent copper atoms from reaching the interlayer dielectric and forming via-to-via leakage current paths therein. In a second aspect, a capping dielectric barrier layer is deposited over the first metal layer prior to sputter etching. During sputter-etching, the capping dielectric barrier layer redistributes on the sidewalls of the interlayer dielectric, preventing sputter-etched copper atoms from reaching the interlayer dielectric and forming via-to-via leakage paths therein. In a third aspect, both a capping dielectric barrier layer and a barrier layer are deposited over the first metal layer prior to sputter-etching to prevent copper atoms produced during sputter-etching from reaching the interlayer dielectric and forming via-to-via leakage paths therein.

Abstract: Internal surfaces of a vacuum chamber are coated with a metal or metal oxide to reduce pump down time and base pressure. The metal is sputter deposited within a partially assembled chamber from a target which comprises the metal. The chamber is then configured to process a substrate such as a silicon wafer.

Abstract: We have discovered that complete copper filling of semiconductor features such as trenches and vias, without the formation of trapped voids, can be accomplished using a copper reflow process when the unfilled portion of the feature structure prior to reflow comprises a capillary within the feature, wherein the volume of the capillary represents between about 20% and about 90%, preferably between about 20% and about 75% of the original feature volume prior to filling with copper. The aspect ratio of the capillary is preferably at least 1.5. The maximum opening dimension of the capillary is less than about 0.8 &mgr;m. The preferred substrate temperature during the reflow process includes it either a soak at an individual temperature or a temperature ramp-up or ramp-down where the substrate experiences a temperature within a range from about 300° C. to about 600° C., more preferably between about 300° C. and about 450° C.

Abstract: Metallization process sequences are provided for forming reliable interconnects including lines, vias and contacts. An initial barrier layer, such as Ta or TaN, is first formed on a patterned substrate followed by seed layer formed using high density plasma PVD techniques. The structure is then filled using either 1) electroplating, 2) PVD reflow, 3) CVD followed by PVD reflow, or 4) CVD.