Abstract:
A conductive plastic lead frame and method of manufacturing the same, suitable for use in IC packaging. In a preferred embodiment, the lead frame is constructed of a plastic or polymer based lead frame structure with an intrinsic conductive polymer coating. In a second embodiment, the lead frame is a composite plastic or polymeric material intermixed with an intrinsic conductive polymer coating.
Abstract:
A high-resolution pressure-sensing device is disclosed. The device includes an insulating flexible matrix having a plurality of filler particles. Application of a force to the matrix causes compression of the matrix. This results in the filler particles occupying a greater amount of space within the matrix relative to when no force is applied. A detector attached to the matrix detects or measures the volume of the filler particles relative to the volume of the matrix, and therefore determines the force applied to the matrix. Preferably, the resistivity of the matrix is inversely proportional to the volume percent of the filler particles, in which case the detector is a resistance-measuring circuit.
Abstract:
Methods are provided to improve the adhesive bonding of a semiconductor die to a substrate through an adhesive paste by forming a layer of silicon dioxide on the back surface of the semiconductor die prior to applying the adhesive paste. Contacting the semiconductor die with ozone, in a gas mixture or in a mixture with water provides rapid oxidation of the silicon layer at the back of the semiconductor die to a silicon dioxide layer of at least 10 angstroms thick, which is sufficient to greatly improve bonding to the adhesive. The formation of a silicon dioxide surface layer prior to application of the adhesive is particularly beneficial when combined with rapid, snap curing processes, where the adhesive can be reliably cured by heating the semiconductor die for less than about 1 minute.
Abstract:
A semiconductor package includes a substrate, a die attached and wire bonded to the substrate, and a die encapsulant encapsulating the die. The die includes a circuit side having a pattern of die contacts, planarized wire bonding contacts bonded to the die contacts, and a planarized polymer layer on the circuit side configured as stress defect barrier. A method for fabricating the package includes the steps of forming bumps on the die, encapsulating the bumps in a polymer layer, and then planarizing the polymer layer and the bumps to form the planarized wire bonding contacts. The method also includes the steps of attaching and wire bonding the die to the substrate, and then forming the die encapsulant on the die.
Abstract:
An apparatus and method for preventing damage to tape attachment semiconductor assemblies due to encapsulation filler particles causing damage to a semiconductor die active surface and/or to a corresponding semiconductor substrate surface by providing an adhesive tape which extends across areas of contact between the semiconductor die active surface and the semiconductor substrate. The present invention also includes extending the adhesive tape beyond the areas of contact between the semiconductor die active surface and the semiconductor substrate to provide a visible surface of visual inspection of proper adhesive tape placement.
Abstract:
An interposer in a BGA or similar package includes a polymide core and a filler of thermally conductive, electrically nonconductive filler. The interposer has a higher thermal conductivity as compared to conventional interposers, thereby increasing the thermal dissipation through the interposer and enabling the device to cool more efficiently. The filler also reduces the coefficient of thermal expansion of the interposer to more closely match the die and reduce stresses. Furthermore, the filler increases the rigidity of the interposer, thereby enabling the interposer to be handled and carried more easily, for example, without a metal frame carrier.
Abstract:
A method for securing two or more semiconductor device components to one another is provided. A hybrid adhesive material, including a pressure-sensitive component and a thermoset component, is used to at least temporarily secure the semiconductor device components to each other. The pressure-sensitive component of the hybrid adhesive material temporarily secures the semiconductor device components to one another. When the semiconductor device components are properly aligned, the hybrid adhesive material may be heated to cure the thermoset component thereof and to more permanently secure the semiconductor device components to one another. The cure temperature may be lower than about 200° C. and as low as about 120° C. or less. A system for effecting the method of the present invention is also disclosed, as well as semiconductor device assemblies that include the hybrid adhesive material.
Abstract:
An adhesive composition and methods incorporating the adhesive composition in semiconductor applications are provided. The adhesive composition is an instant setting adhesive composition that does not require external energy input such as heat or radiation such for application of the adhesive composition on a surface. The instant setting composition possesses sufficient thixotropic characteristics such that applying the instant setting adhesive composition to a surface can be accomplished by a variety of application techniques and in a variety of patterns. Once applied to the surface, the instant setting adhesive composition sets to retain the discrete pattern as applied, in a relatively short period of time, typically from about 0.10 to about 120 seconds at an ambient temperature, typically from 20° C. to 30° C. Advantageously, the instant setting adhesive composition can be screen printed on a semiconductor wafer prior to singulation because streets between the dice are essentially free of the instant setting adhesive composition.
Abstract:
A high-resolution pressure-sensing device is disclosed. The device includes an insulating flexible matrix having a plurality of filler particles. Application of a force to the matrix causes compression of the matrix. This results in the filler particles occupying a greater amount of space within the matrix relative to when no force is applied. A detector attached to the matrix detects or measures the volume of the filler particles relative to the volume of the matrix, and therefore determines the force applied to the matrix. Preferably, the resistivity of the matrix is inversely proportional to the volume percent of the filler particles, in which case the detector is a resistance-measuring circuit.
Abstract:
A method and apparatus for improved stencil/screen print quality is disclosed. The stencil or screen assists in application of a printable material onto a substrate, such as an adhesive to a semiconductor die of a semiconductor wafer during a lead-on-chip (LOC) packaging process. In one embodiment, the stencil includes a coating applied to at least one surface of a pattern of the stencil or screen to retard running of the printable material onto the surface. In another embodiment, the stencil or screen includes a second coating applied to at least one other surface of the pattern to promote spreading of the printable material onto the substrate.