Abstract:
A BGA package and a method for fabricating the package are provided. The package includes a semiconductor die, internal conductors wire bonded to bond pads on the die, external ball contacts attached to ball bonding pads formed on the conductors in a dense grid pattern, and an encapsulating resin encapsulating the die and conductors. The package is fabricated using a lead frame having lead fingers that form the conductors. The die is back bonded to a polymer tape placed across the lead fingers, and then wire bonded to bonding pads on the conductors. In addition, the encapsulating resin is molded to include openings for the ball contacts which are aligned with the ball bonding pads. An alternate embodiment BGA package includes a polymer substrate adhesively bonded to a face of the die. The polymer substrate includes conductors having beam leads aligned with an opening through the polymer substrate. The opening provides access for a bonding tool for bonding bumps on the beam leads to bond pads on the die.
Abstract:
A semiconductor package, and a method for fabricating the package are provided. The package includes a plastic body, and a pair of stacked semiconductor dice encapsulated in the plastic body, and wire bonded to separate leadframe segments. A first leadframe segment includes lead fingers configured to support a first semiconductor die of the stacked pair, and to form terminal leads of the package. A second leadframe segment is attached to the first leadframe segment, and includes lead fingers that support a second semiconductor die of the stacked pair. The lead fingers of the second leadframe are in physical and electrical contact with the leadfingers of the first leadframe. In addition, tip portions of the lead fingers of the first leadframe segment are staggered relative to tip portions of the lead fingers of the second leadframe segment to provide space for bond wires. The lead fingers support the dice during encapsulation, and also provide a heat conductive path for transferring heat from the dice during operation. The package can be constructed using lead-on-chip leadframes and conventional semiconductor packaging equipment.
Abstract:
A method for packaging a semiconductor device includes connecting a plurality of wire leads to a corresponding plurality of electrical connection pads on the semiconductor device, covering at least a portion of the semiconductor device and at least a portion of each of the wire leads with an encapsulating material, and removing a portion of the encapsulating material and a portion of each of the wire leads to form a packaged semiconductor device wherein each of the wire leads has an exposed portion only at an end. The invention also includes a packaged semiconductor device having an integrated circuit device with a plurality of electrical connection pads, a plurality of wire leads coupled to the plurality of electrical connection pads, and a covering of encapsulating material covering at least a portion of the integrated circuit device and covering each of the wire leads, wherein each of the wire leads has an exposed end. The present invention contemplates wire bonding and encapsulation of individual die as well as multiple die on a single wafer.
Abstract:
An improved method for attaching a semiconductor die to a leadframe is provided The improved method comprises forming a patterned adhesive layer on a side of a semiconductor wafer prior to singulation of the dies from the wafer. The adhesive layer is patterned such that wire bonding pads on the dies, as well as the streets between the dies, are free of adhesive material The adhesive layer may be deposited and patterned using a hot or cold screen printing process, by depositing and photopatterning a photosensitive adhesive, or using a resist etch back method. During a packaging process for attaching a die to a leadframe, the adhesive layer is heated and the lead fingers of the leadframe are placed in contact with the die under pressure. In an alternate embodiment of the invention, the lead fingers, rather than a side of the dies, are coated with an adhesive layer.
Abstract:
A semiconductor device assembly and method of making the device are disclosed. The assembly comprises a semiconductor die attached to an electrically conductive layer, which is, in turn, connected to a dielectric layer carrying conductive traces of the electrical connection layer. The conductive traces provide connection between an array of discrete conductive elements and bonding wires connected to bond pads of the die. The conductive layer enhances thermal conduction and structural stiffness for the assembly. In addition, the conductive layer provides a voltage reference plane that may be connected to a power source, a ground source, or an intermediate reference voltage. The conductive layer also includes at least one electrical current isolation slot, which segments the conductive layer to help isolate noise induced in one segment of the conductive layer from the other segments.
Abstract:
A method for securing a semiconductor device to a carrier substrate includes inserting a semiconductor device with a plurality of stub contacts extending from a bottom edge thereof into a receptacle of an alignment device associated with the carrier substrate. Upon attachment of the alignment device to a carrier substrate and insertion of a vertically mountable semiconductor device into the receptacle, the semiconductor device is biased so as to establish and maintain electrical communication between the semiconductor device and the carrier substrate.
Abstract:
A semiconductor device package including leads with substantially planar exposed portions extending from a bottom edge of the package. The exposed portions of the leads may comprise stub contacts extending perpendicularly from the bottom edge. The exposed portions of the leads may be substantially rigid or nondeformable. A complementary alignment device that may be used with the semiconductor device package may include a receptacle for receiving the semiconductor device package.
Abstract:
A method of using adhesive tape to temporarily retain a die being temporarily held in a fixture during testing and burn-in. The method of the present invention uses a die cut piece of adhesively coated tape to hold a die in a test and burn-in fixture. Upon subsequent heating of the tape beyond the normal operating range of the adhesive coating on the tape, the die is removed from the tape, the tape is removed from the test and burn-in fixture, and the remaining adhesive, if any, is removed from the test and burn-in fixture.
Abstract:
A semiconductor package includes a substrate, and a semiconductor die flip chip mounted to the substrate. The package also includes substrate circuitry on a circuit side of the substrate, die circuitry on a back side of the die, terminal contacts on the die circuitry, bonded connections between the substrate circuitry and the die circuitry, and an encapsulant on the bonded connections and edges of the die. The die can include an image sensor on the circuit side configured to receive electromagnetic radiation transmitted through the substrate. A method for fabricating the package includes the step of providing a wafer with multiple dice, forming the die circuitry on the dice, and singulating the wafer into individual dice. The method also includes the steps of providing a substrate panel with multiple substrates, forming the substrate circuitry on the substrates, flip chip bonding the dice to the substrates, forming bonded connections between the dice and the substrates, forming the terminal contacts on the die circuitry, and singulating the panel into separate components.
Abstract:
The present invention is directed to a method of attaching a leadframe to a singulated good die using a wet film adhesive applied in a predetermined pattern on the active surface of the good die, the lead finger of a leadframe, or both. By applying the adhesive only to identified good dice, time and material are saved over a process that applies adhesive to the entire wafer. By attaching the leadframe to the good die with a wet film, it is possible to remove the leadframe from the good die for rework if the good die subsequently tests unacceptable.