Abstract:
A method for determining the electromigration characteristics of a wiring structure in an integrated circuit device is disclosed. In an exemplary embodiment of the invention, the method includes configuring a defined test structure type for the integrated circuit device. The defined test structure type further includes a first line of wiring primarily disposed in a principal plane of a semiconductor substrate, and a second line of wiring connected to the first line of wiring. The second line of wiring is disposed in a secondary plane which is substantially parallel to the principal plane, with the first and second lines of wiring being connected by a via structure therebetween. A thermal coefficient of resistance for the first line of wiring and the via structure is determined, and a wafer-level stress condition is introduced in a first individual test structure of the defined test structure type. Then, at least one parameter value for is determined for the first individual test structure, which parameter value is used to predict a lifetime projection for the wiring structure in the integrated circuit device.
Abstract:
Lateral cathode field emission devices and methods of fabrication are set forth. Conventional integrated circuit fabrication techniques are advantageously used to produce the lateral FEDs. Cathode tips on the order of several hundred angstroms are consistently obtained as well as exact spacing of the cathode to gate and cathode to anode. Various cathode and device configurations are described, including a circular field emission device. A single integrated structure having multiple cathodes and multiple gates is possible to perform various logic operations and/or enhance current output from the device. Multiple field effect devices, with cathodes disposed parallel or perpendicular to the substrate, are integrally coupled through a sharing of one or more metallization layers definitive of the elements of the devices. Significant advantages in current density and circuit layout can be obtained. Methods for fabricating the various devices are also explained.
Abstract:
Various embodiments include methods of forming interconnect structures, and the structures formed by such methods. In one embodiment, a method can include: providing a precursor interconnect structure having: a photosensitive polyimide (PSPI) layer; a controlled collapse chip connection (C4) bump overlying the PSPI layer; and a solder overlying the C4 bump and contacting a side of the C4 bump. The method can further include recessing a portion of the PSPI layer adjacent to the C4 bump to form a PSPI pedestal under the C4 bump. The method can additionally include forming an underfill abutting the PSPI pedestal and the C4 bump, wherein the underfill and the solder form an interface separated from the PSPI pedestal.
Abstract:
A liner-to-liner direct contact is formed between an upper metallic liner of a conductive via and a lower metallic liner of a metal line below. The liner-to-liner contact impedes abrupt electromigration failures and enhances electromigration resistance of the metal interconnect structure. The at least one dielectric material portion may include a plurality of dielectric material portions arranged to insure direct contact of between the upper metallic liner and the lower metallic liner. Alternatively, the at least one dielectric material portion may comprise a single dielectric portion of which the area has a sufficient lateral overlap with the area of the conductive via to insure that a liner-to-liner direct contact is formed within the range of allowed lithographic overlay variations.
Abstract:
Interconnect structures and methods of fabricating the same are provided. The interconnect structures provide highly reliable copper interconnect structures for improving current carrying capabilities (e.g., current spreading). The structure includes an under bump metallurgy formed in a trench. The under bump metallurgy includes at least: an adhesion layer; a plated barrier layer; and a plated conductive metal layer provided between the adhesion layer and the plated barrier layer. The structure further includes a solder bump formed on the under bump metallurgy.
Abstract:
Various embodiments include methods of forming interconnect structures, and the structures formed by such methods. In one embodiment, a method can include: providing a precursor interconnect structure having: a photosensitive polyimide (PSPI) layer; a controlled collapse chip connection (C4) bump overlying the PSPI layer; and a solder overlying the C4 bump and contacting a side of the C4 bump. The method can further include recessing a portion of the PSPI layer adjacent to the C4 bump to form a PSPI pedestal under the C4 bump. The method can additionally include forming an underfill abutting the PSPI pedestal and the C4 bump, wherein the underfill and the solder form an interface separated from the PSPI pedestal.
Abstract:
A solder interconnect structure is provided with non-wettable sidewalls and methods of manufacturing the same. The method includes forming a nickel or nickel alloy pillar on an underlying surface. The method further includes modifying the sidewall of the nickel or nickel alloy pillar to prevent solder wetting on the sidewall.
Abstract:
Structures and methods for detecting solder wetting of pedestal sidewalls. The structure includes a semiconductor wafer having an array of integrated circuit chips, each of the integrated circuit chips having an array of chip pedestals having respective chip solder columns on top of the chip pedestals, the pedestals spaced apart a first distance in a first direction and a spaced apart second distance in second direction perpendicular to the first direction; and at least one monitor structure disposed in different regions of the wafer from the integrated circuit chips, the monitor structure comprising at least a first pedestal and a first solder column on a top surface of the first pedestal and a second pedestal and a second solder column on a top surface of the second pedestal, the first and the second pedestals spaced apart a third distance, the third distance less than the first and the second distances.
Abstract:
The invention provides a semiconductor chip structure having at least one aluminum pad structure and a polyimide buffering layer under the aluminum pad structure, wherein the polyimide buffering layer is self-aligned to the aluminum pad structure, and a method of forming the same. The method includes forming a polyimide buffering layer on a substrate, forming an aluminum pad structure on the buffering layer, and, using the aluminum pad structure as a mask, etching the substrate to remove the polyimide buffering layer from the substrate everywhere except under the aluminum pad structure.
Abstract:
A method of connecting chips to chip carriers, ceramic packages, etc. (package substrates) forms smaller than usual first solder balls and polymer pillars on the surface of a semiconductor chip and applies adhesive to the distal ends of the polymer pillars. The method also forms second solder balls, which are similar in size to the first solder balls, on the corresponding surface of the package substrate to which the chip will be attached. Then, the method positions the surface of the semiconductor chip next to the corresponding surface of the package substrate. The adhesive bonds the distal ends of the polymer pillars to the corresponding surface of the package substrate. The method heats the first solder balls and the second solder balls to join the first solder balls and the second solder balls into solder pillars.