Abstract: Methods for releasably attaching sacrificial support members to microfeature workpieces and microfeature devices formed using such methods are disclosed herein. One embodiment, for example, is directed to a method for processing a microfeature workpiece releasably attached to a first support member. The workpiece includes a microelectronic substrate, a plurality of microelectronic dies on and/or in the substrate, and a sacrificial support member attached to an active side of the substrate. The method can include separating individual dies from the workpiece by cutting through the sacrificial support member and the substrate while the workpiece is attached to the first support member. The method can also include attaching a singulated die and corresponding portion of the sacrificial support member as a unit to a second support member.

Abstract: A method of attaching solder balls to a BGA package using a ball pickup tool is disclosed. An array of solder balls is formed on a first substrate for interconnecting with conductive sites on another substrate. The ball pickup tool picks up solder balls with a vacuum suction from a fluidized ball reservoir and utilizes a puff of gas to release the solder ball(s) carried thereon to conductive sites of a substrate for bonding thereto. In another embodiment, the bond pads of a substrate are coated with a flux or adhesive and lowered into a fluidized ball reservoir for direct attachment of solder balls.

Abstract: System for placing conductive spheres on prefluxed bond pads of a substrate using a stencil plate with a pattern of through-holes positioned over the bond pads. Conductive spheres are placed in the through-holes by a moving feed mechanism and the spheres drop through the through-holes onto the bond pads. In one embodiment, the feed mechanism is a sphere hopper which crosses the entire through-hole pattern. In another embodiment, a shuttle plate fed spheres from a reservoir and reversibly moves about one-half of the pitch, moving from a non-discharge position to a discharge position.

Abstract: A method for increasing integrated circuit density is disclosed comprising stacking an upper wafer and a lower wafer, each of which having fabricated circuitry in specific areas on their respective face surfaces. The upper wafer is attached back-to-back with the lower wafer with a layer of adhesive applied over the back side of the lower wafer. The wafers are aligned so as to bring complementary circuitry on each of the wafers into perpendicular alignment. The adhered wafer pair is then itself attached to an adhesive film to immobilize the wafer during dicing. The adhered wafer pair may be diced into individual die pairs or wafer portions containing more than one die pair.

Abstract: Methods for releasably attaching sacrificial support members to microfeature workpieces and microfeature devices formed using such methods are disclosed herein. One embodiment, for example, is directed to a method for processing a microfeature workpiece releasably attached to a first support member. The workpiece includes a microelectronic substrate, a plurality of microelectronic dies on and/or in the substrate, and a sacrificial support member attached to an active side of the substrate. The method can include separating individual dies from the workpiece by cutting through the sacrificial support member and the substrate while the workpiece is attached to the first support member. The method can also include attaching a singulated die and corresponding portion of the sacrificial support member as a unit to a second support member.

Abstract: Apparatus for placing conductive spheres on prefluxed bond pads of a substrate using a stencil plate with a pattern of through-holes positioned over the bond pads. Conductive spheres are placed in the through-holes by a moving feed mechanism and the spheres drop through the through-holes onto the bond pads. In one embodiment, the feed mechanism is a sphere hopper which crosses the entire through-hole pattern. In another embodiment, a shuttle plate fed spheres from a reservoir and reversibly moves about one-half of the pitch, moving from a non-discharge position to a discharge position.

Abstract: An apparatus and method for increasing integrated circuit density comprising an upper die and a lower die, the latter preferably a flip chip, which are connected to a conductor-carrying substrate or a leadframe. The upper die is attached back-to-back to the lower die with a layer of adhesive applied over the back side of the lower die. Bond wires or TAB leads are attached between bond pads on the upper die and corresponding conductive trace or lead ends on the substrate. The upper die may be smaller than the lower die such that a small discrete component such as a resistor, capacitor, or the like can be attached to the adhesive not covered by the upper die. Bond wires can be attached between the upper die and the component, as well as between the component and the substrate. One or more additional die may be stacked on the upper die and electrically connected to the substrate. Furthermore, multiple lower dice can be arranged on the substrate to support upper dice bridged between the lower dice.

Abstract: An apparatus and method of forming improved wire bonds between the contact pads on semiconductor devices and individual lead frame fingers of a lead frame. The apparatus and method include the use of a penetrating individual independent lead finger clamp during the wire bonding process to provide increased stability of the individual lead finger for improved bonding by the clamp penetrating a portion of the lead finger being bonded. If desired, the apparatus and method also provide for the use of either a penetrating or non-penetrating fixed clamp for the lead fingers during the wire bonding process in addition to the penetrating individual independent lead finger clamp during the wire bonding process to provide increased stability of the individual lead finger for improved bonding.

Abstract: Methods for placing conductive spheres on prefluxed bond pads of a substrate using a stencil plate with a pattern of through-holes positioned over the bond pads. Conductive spheres are placed in the through-holes by a moving feed mechanism and the spheres drop through the through-holes onto the bond pads. In one embodiment, the feed mechanism is a sphere hopper which crosses the entire through-hole pattern. In another embodiment, a shuttle plate fed spheres from a reservoir and reversibly moves about one-half of the pitch, moving from a non-discharge position to a discharge position.

Abstract: A method for increasing integrated circuit density is disclosed comprising stacking an upper wafer and a lower wafer, each of which having fabricated circuitry in specific areas on their respective face surfaces. The upper wafer is attached back-to-back with the lower wafer with a layer of adhesive applied over the back side of the lower wafer. The wafers are aligned so as to bring complementary circuitry on each of the wafers into perpendicular alignment. The adhered wafer pair is then itself attached to an adhesive film to immobilize the wafer during dicing. The adhered wafer pair may be diced into individual die pairs or wafer portions containing more than one die pair.

Abstract: An apparatus for supporting lead fingers during a wire bonding process and method of preventing the bonding apparatus and clamping assembly from applying force against the die. The present invention includes the use of a movable arm with a portion that is positionable under a portion of the lead fingers of a lead frame during the wire bonding process to provide increased stability of the lead fingers and prevent the bonding apparatus and clamping assembly from applying force against the die. The present invention also provides for the transfer of heat from the heat block directly to the lead fingers during the wire bonding process. The present invention includes the use of a clamp for stabilizing lead fingers during the wire bonding process.

Abstract: A method of attaching solder balls to a BGA package using a ball pickup tool is disclosed. An array of solder balls is formed on a first substrate for interconnecting with conductive sites on another substrate. The ball pickup tool picks up balls with a vacuum suction from a fluidized ball reservoir and utilizes a puff of gas to release the solder ball(s) carried thereon to conductive sites of a substrate for bonding thereto. In another embodiment, the bond pads of a substrate are coated with a flux or adhesive and lowered into a fluidized ball reservoir for direct attachment of solder balls.

Abstract: A semiconductor device, such as an integrated circuit die, includes a plurality of bond pads on an active surface thereof electrically connected to internal circuitry of the semiconductor device, and a plurality of jumper pads on the active surface which are electrically isolated from internal circuitry of the die. The jumper pads effectively provide stepping stones for wire bonds to be made across the active surface between bond pads. The jumper pads may be formed directly on the semiconductor device or on a nonconductive support structure that is attached to the semiconductor device.

Abstract: A method and apparatus are disclosed for mounting a wafer on a mount and thinning the wafer. The wafer includes a front surface having bumps with an adhesive tape having a backing attached thereto and a back surface. The front surface of the wafer is mounted facedown on a suction surface with the backing of the adhesive tape abutting the surface. The wafer is then suctioned, after which the back surface of the wafer undergoes a grinding process to thin the wafer. Since the backing attached to the bumps on the wafer is substantially planar and sits substantially flat on the suction surface of the wafer mount, the force exerted on the wafer from the thinning process does not overcome the suction force holding the wafer on the wafer mount. Thus, the bumped wafer may be thinned without damaging the bumps and the active surface of the wafer.

Abstract: A wire-bonding machine includes a heat block for supporting a lead frame during wire-bonding. A clamp mechanism in the machine clamps leads of the lead frame during wire-bonding by fixedly holding sets of the leads against the heat block one set at a time. A wire-bonding tool wire-bonds leads clamped by the clamp mechanism to bond pads on an integrated circuit die. By clamping leads of the lead frame in separate sets, the machine provides improved clamping for lead frames with leads requiring clamping in different planes.

Abstract: An offset die stacking arrangement is disclosed having at least one upper level die having a width which is less than the distance separating the opposing bonding sites of the underlying die. The upper die is fixed above the lower die and rotated within a plane parallel to the lower die through an angle which insures that none of the bonding sites of the lower die are obstructed by the upper die. Once the dice are fixed in this manner, the entire assembly is subjected to the wire bonding process with all of the bonds being made in the same step.

Abstract: A method of forming conductive structures on the contact pads of a substrate,such as a semiconductor die or a printed circuit board. A solder mask is secured to an active surface of the substrate. Apertures through the solder mask are aligned with contact pads on the substrate. The apertures may be preformed or formed after a layer of the material of which the solder mask is comprised has been disposed on the substrate. Conductive material is disposed in and shaped by the apertures of the solder mask to form conductive structures in communication with the contact pads exposed to the apertures. Sides of the conductive structures are exposed through the solder mask, either by removing the solder mask from the substrate or by reducing the thickness of the solder mask. The present invention also includes semiconductor devices formed during different stages of the method of the present invention.

Abstract: An apparatus and method of forming improved wire bonds between the contact pads on semiconductor devices and individual lead frame fingers of a lead frame. The present invention includes the use of an individual independent lead finger clamp during the wire bonding process to provide increased stability of the individual lead finger for improved bonding. If desired, the present invention also provides for the use of a conventional fixed clamp for the lead fingers during the wire bonding process in addition to the individual independent lead finger clamp during the wire bonding process to provide increased stability of the individual lead finger for improved bonding. The present invention also contemplates the replacement of the fixed clamp with another, or second, independent clamp in addition to the first individual independent lead finger clamp during the wire bonding process.

Abstract: A method of attaching solder balls to a BGA package using a ball pickup tool. An array of solder balls is formed on a first substrate for interconnecting with conductive sites on another substrate. The ball pickup tool picks up balls with a vacuum suction from a fluidized ball reservoir and utilizes a puff of gas to release the solder ball(s) carried thereon to conductive sites of a substrate for bonding thereto. In another embodiment, the bond pads of a substrate are coated with a flux or adhesive and lowered into a fluidized ball reservoir for direct attachment of solder balls.

Abstract: A multiple stacked die device is disclosed that contains up to four dies and does not exceed the height of current single die packages. Close-tolerance stacking is made possible by a low-loop-profile wire-bonding operation and thin-adhesive layer between the stacked dies.