Abstract:
A process for improving the adhesion between an underlying copper structure, and overlying materials and structures, has been developed. The process features formation of a tantalum nitride layer on a copper structure, wherein the copper structure is located in a damascene type opening. To obtain the maximum adhesion benefit the tantalum nitride layer is formed via an atomic deposition layer procedure, performed at specific deposition conditions. The adhesion between the underlying copper structure and overlying materials such as a silicon nitride etch stop layer, as well the adhesion between the lower level copper structure and overlying upper level metal interconnect structures, is improved as a result of the presence of the atomic layer deposited tantalum nitride layer.
Abstract:
An opening in a dielectric layer having a unique barrier layer structure is provided. In an embodiment, the opening is a via and a trench. The barrier layer, which may comprise one or more barrier layers, is formed such that the ratio of the thickness of the barrier layers along a sidewall approximately midway between the bottom of the trench and the top of the dielectric layer to the thickness of the barrier layers along the bottom of the trench is greater than about 0.55. In another embodiment, the ratio of the thickness of the barrier layers along a sidewall approximately midway between the bottom of the trench and the top of the dielectric layer to the thickness of the barrier layers along the bottom of the via is greater than about 1.0. An underlying conductive layer may be recessed.
Abstract:
An opening in a semiconductor device with improved step coverage. The opening comprises a dielectric layer overlying a substrate, having at least one via opening to expose the substrate. The via opening comprises a step region in the upper portion of the via opening and a concave profile region with respect to the dielectric layer in the lower portion of the via opening. A semiconductor device with the opening is also disclosed.
Abstract:
An opening in a dielectric layer having a unique barrier layer structure is provided. In an embodiment, the opening is a via and a trench. The barrier layer, which may comprise one or more barrier layers, is formed such that the ratio of the thickness of the barrier layers along a sidewall approximately midway between the bottom of the trench and the top of the dielectric layer to the thickness of the barrier layers along the bottom of the trench is greater than about 0.55. In another embodiment, the ratio of the thickness of the barrier layers along a sidewall approximately midway between the bottom of the trench and the top of the dielectric layer to the thickness of the barrier layers along the bottom of the via is greater than about 1.0. An underlying conductive layer may be recessed.
Abstract:
A composite barrier layer provides 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 are generally disposed to form boundaries with dielectric materials and crystalline layers are generally disposed to form boundaries with conductive materials such as interconnect materials.
Abstract:
It is a general object of the present invention to provide an improved method of fabrication in the formation of an improved copper metal diffusion barrier layer having the structure, W/WSiN/WN, in single and dual damascene interconnect trench/contact via processing with 0.10 micron nodes for MOSFET and CMOS applications. The diffusion barrier is formed by depositing a tungsten nitride bottom layer, followed by an in situ SiH4/NH3 or SiH4/H2 soak forming a WSiN layer, and depositing a final top layer of tungsten. This invention is used to manufacture reliable metal interconnects and contact vias in the fabrication of MOSFET and CMOS devices for both logic and memory applications and the copper diffusion barrier formed, W/WSiN/WN, passes a stringent barrier thermal reliability test at 400° C. Pure single barrier layers, i.e., single layer WN, exhibit copper punch through or copper spiking during the stringent barrier thermal reliability test at 400° C.
Abstract:
A method of electrochemical deposition (ECD) provides a barrier and a seed layer on a substrate. The surfaces of the substrate are pre-treated before a metal layer is electrochemically deposited thereon in an electrochemical plating cell with a physical or a chemical surface treatment process. The electrochemical plating cell is covered by a cap to prevent evaporation of the electrolyte solution. The electrochemical plating cell includes a substrate holder assembly with a lift seal, e.g., with a contact angle θ less than 90° between the lift seal and the substrate. The substrate holder assembly includes a substrate chuck at the rear side of the substrate.
Abstract:
A loadlock. The loadlock for wafers includes a chamber, a pedestal, a retractable shaft, and a bellows. The chamber has a plurality of walls and a bottom surface. The pedestal supports a cassette and is disposed in the chamber. The retractable shaft has a top end and a bottom end. The top end is connected to the pedestal and the bottom end is connected to the bottom surface as a reference for positioning the pedestal. The bellows has a first end and a second end. The first end is disposed on the pedestal and the second end is sealed at the bottom end of the retractable shaft. Preferably, the retractable shaft is fully enclosed by the bellows.
Abstract:
A method of forming a via in a low-k dielectric material and without the attendant via poisoning problem, or a dual damascene structure formed in the same dielectric and without the same problem are disclosed. The vertical walls of the via opening are first lined with a low-k protection layer and then covered with a barrier layer in order to prevent outgassing from the low-k dielectric material when copper is deposited into the via opening. In the case of a dual damascene structure, it is sufficient that the hole opening underlying the trench opening is first lined with the low-k protection layer. The resulting via or dual damascene structure is free of poisoned metal and, therefore, more reliable.
Abstract:
A new method is provided is creating metal interconnect comprising copper. A first embodiment of the invention provides for the application of a doped layer of copper. A second embodiment of the invention provides for the deposition of a silicon nitride layer as an inter-barrier film over surfaces of an opening created in a layer of dielectric followed by removing the layer of silicon nitride from the bottom of the opening followed by depositing a doped copper-alloy seed layer over surfaces of the opening followed by plating a layer of copper over the copper-alloy seed layer.