Abstract: An apparatus and method are shown for indexing magazines and molded leadframes within the magazines comprising a lateral drive portion coupled to and located below the magazines for selectively moving a selected one of the magazines laterally at a first speed and for simultaneously moving the rest of the magazines laterally at a second speed, and a vertical drive portion having a portion for insertion into the selected one of the magazines when the magazines have ceased moving laterally for selectively moving the molded leadframes vertically within the selected one of the magazines. A plurality of magazine retaining members are also included each having a portion inserted into a portion of the lateral drive portion, and each having a cavity wherein a base portion of a corresponding one of the magazines rests.

Abstract: A post mold curing apparatus for use in association with a molding line system for providing plastic encapsulated semiconductor chips mounted on leadframes is disclosed which includes a leadframe carrier having a rotary, substantially cylindrical shaped assembly for containing and moving a plurality of semiconductor chips and their associated leadframe strips into both an elevated temperature post mold curing region and into a lower temperature cool-down region. Each of the leadframe strips with their associated semiconductor chips are sequentially inserted into cavity regions located in the cylindrical assembly to assist in moving each of the plurality of leadframe strips through the elevated temperature post mold curing region, and subsequently, each of the leadframe strips with their associated semiconductor chips are removed from the cavity regions after passing through the lower temperature cool-down region.

Abstract: An automatic plunger apparatus and method therefor is disclosed for compressing molten plastic into a cavity for forming an encapsulated semiconductor device. A compressing device drives a plunger member in order to compress and direct molten plastic to flow in a forward direction into the cavity. An overload compensator is coupled to the plunger member for permitting the plunger member to withdraw in a reverse direction when the plunger member is prevented from compressing and directing the molten plastic to flow in the forward direction into the cavity. The overload compensator comprises a first member retained within a second member for transferring the force from the compressing device into motion of the plunger member.

Abstract: An automatic pellet feeding apparatus and method for delivering plastic pellets to a plastic molding machine for encapsulating semiconductor chips stores a plurality of plastic pellets for ultimate delivery to the plastic molding machine. A stair like structure is provided for vertically moving the plastic pellets from a plastic pellet storage location to a conveyor which moves the plastic pellets to the plastic molding machine. The stair like structure has an arrangement of members which alternates between a movable member and a stationary member. The movable members are all moved up and down together, and when the movable members are down, plastic pellets may be loaded thereon from either the storage location or from an adjacent stationary member. Alternatively, when the movable members are up, plastic pellets may be off-loaded therefrom to either an adjacent stationary member or to the conveyor.

Abstract: A post mold curing apparatus for use in association with a molding line system for providing plastic encapsulated semiconductor chips mounted on leadframes is disclosed which includes a leadframe carrier having a rotary, substantially cylindrical shaped assembly for containing and moving a plurality of semiconductor chips and their associated leadframe strips into both an elevated temperature post mold curing region and into a lower temperature cool-down region. Each of the leadframe strips with their associated semiconductor chips are sequentially inserted into cavity regions located in the cylindrical assembly to assist in moving each of the plurality of leadframe strips through the elevated temperature post mold curing region, and subsequently, each of the leadframe strips with their associated semiconductor chips are removed from the cavity regions after passing through the lower temperature cool-down region.

Abstract: A leadframe strip is provided with a die pad and a protrusion is formed on the die pad so as to project from the rear side thereof. An integrated circuit chip is bonded to the front side of the die pad and is connected by leads to portions of the leadframe strip adjacent the die pad. The die pad, chip and leads are placed in a mold and an epoxy is injected into the mold to encapsulate the die pad, chip and leads. The protrusion spaces the die pad from the internal mold surface confronting the rear side of the die pad.

Abstract: An electromechanical press apparatus for trimming excess portions from a leadframe strip package having a semiconductor chip thereon and for forming leads of the leadframe strip package extending from the semiconductor chip is disclosed. The apparatus provides an electric motor that drives two orthogonally oriented shafts through a 90 degree gear box coupler. One shaft is used to move a portion-of the apparatus along a rectangular path of motion for linearly shifting a leadframe strip along a plane orthogonally oriented to the rectangular path of motion. The other shaft is used to move another portion of the apparatus along a line of motion orthogonally oriented to the plane for performing a trimming operation or a forming operation.

Abstract: An electromechanical press apparatus for trimming excess portions from a leadframe strip package having a semiconductor chip thereon and for forming leads of the leadframe strip package extending from the semiconductor chip is disclosed. The apparatus provides an electric motor that drives two orthogonally oriented shafts through a 90 degree gear box coupler. One shaft is used to move a portion of the apparatus along a rectangular path of motion for linearly shifting a leadframe strip along a plane orthogonally oriented to the rectangular path of motion. The other shaft is used to move another portion of the apparatus along a line of motion orthogonally oriented to the plane for performing a trimming operation or a forming operation.

Abstract: An automatic plunger apparatus is disclosed for compressing molten plastic into a cavity for forming an encapsulated semiconductor device. A compressing device drives a plunger member in order to compress and direct molten plastic to flow in a forward direction into the cavity. An overload compensator is coupled to the plunger member for permitting the plunger member to withdraw in a reverse direction when the plunger member is prevented from compressing and directing the molten plastic to flow in the forward direction into the cavity. The overload compensator includes a first member retained within a second member for transferring the force from the compressing device into motion of the plunger member.

Abstract: A modular electromechanical press apparatus and method for using such an apparatus for trimming excess portions from a leadframe strip package having a semiconductor chip thereon and for forming leads of the leadframe extending from the semiconductor chip is disclosed. The apparatus provides an electric motor for driving a plurality of coupled shafts. Two of the shafts include flywheels for reducing the load on the motor once the shafts reach steady state rotational velocity. In addition, each of these two shafts are provided with a one stroke clutch, so that upon activation of the clutches, one shaft moves a leadframe strip into proper position, and the other shaft drives a tool at the proper time to execute the desired trimming or forming operation. The unique arrangement of the components of the apparatus provides maximum power in a minimum size unit that can easily be incorporated into an in-line system for producing semiconductor packages.

Abstract: A semiconductor device comprising a semiconductor unit with leads extending therefrom is placed on a bottom packaging tray having a die-shaped upper surface. A top lubricating type film is used over the device 10 and below a punch unit that is used to bend the leads. A process of assembling the semiconductor device on a die type package is disclosed which includes placing the semiconductor device with leads on a packaging tray with upper lead-shaped baring surfaces, placing an anti-friction film sheet over the tray and over the device with its leads extending therefrom, and actuating a punch unit disposed above the film sheet, thereby forming or bending the leads and simultaneously using the die type tray for packaging the semiconductor device.

Abstract: A semiconductor lead frame wherein the chip pad and leads are contained within a separate inner island attached to an outer frame through a plurality of independent connectors spread around the perimeter of the island. Each connector consists of a curved filament capable of compression or expansion, thereby allowing the inner island to undergo some structural deformation without transmitting it to the outer frame. As a result, alignment holes contained in the frame are not affected by mechanical stresses suffered during the molding stage of the packaging operation. Separate alignment apertures may be added to the island portion of the lead frame as additional reference markers for post-molding alignment.

Abstract: A molding apparatus having variable-volume cavities is provided. The apparatus consists of a lower and an upper mold defining a cavity for the lead frame, and having a conduit for forcing fluid plastic from a reservoir to the cavity for encapsulating an integrated circuit bonded to a lead frame. A pressure source is used to force the plastic from the reservoir through the conduit into both the upper and lower portions of the cavity surrounding the lead frame. The cavity of the mold is equipped with at least one piston-like insert slideably mounted in a bore hole in the surface of the cavity. The insert can be compressed or expanded to reduce or increase, respectively, the volume of the cavity. Thus, the final size of the cavity in the mold is determined by the position of the insert at the end of the encapsulation process. By allowing the expansion of the insert during a first phase of the molding operation, excess plastic is forced into the cavity.

Abstract: Standard STEM drilling equipment is utilized to effect the electrochemical removal of material in multiple directions in order to produce cooling holes with turbulator ridges. An initial section of the cooling hole is drilled by displacing the electrode vertically into the turbine blade under conditions that produce a hole with an approximate clearance of 0.3 mm around the electrode. The electrode is then moved horizontally about 0.15 mm toward one side of the wall of the hole, thus leaving a clearance of about 0.45 mm on the other side. Vertical drilling of a second hole section is then resumed by the conventional electrochemical process. Because of the position of the electrode relative to the wall of the hole and the correspondingly different current densities in place along the circumference of the wall, a vertical inset is formed below the initial hole section, which creates a turbulator ridge.

Abstract: An improved lead frame cutting apparatus for integrated circuit packages therefor is disclosed. This apparatus employs symmetrical punches that have multiple cutting edges, and can therefore be positioned to a new cutting edge rather than replacing the punch. These symmetrical punches are used in conjunction with a thin cutting plate, which is also symmetrical, allowing both sides to be used. This thin cutting plate is fabricated using an inexpensive cutting process wherein multiple cutting plates are formed in one operation which saves time and money compared to the machined cutting plate of the prior art. Two versions of the symmetrical punch are disclosed. One version has four cutting surfaces and is used to remove the dam bars on the lead frame of the integrated circuit package. The second version has two cutting surfaces and is used to cut the leads on the lead frame to the proper length.

Abstract: An apparatus for encapsulating an integrated circuit lead frame in plastic is disclosed. This apparatus includes an upper mold and a lower mold which, when properly joined together, define the package area of the lead frame as well as a reservoir for the molten plastic and a conduit and flow pocket for assuring uniform flow of plastic into the package area of the molds. The integrated circuit lead frame has a flow hole to allow the molten plastic to flow from the conduit into the flow pocket and into the bottom portion of the package area. The conduit also allows the molten plastic to flow directly to the top portion of the package area. With the plastic being more uniformly injected into both (top and bottom) package or cavity areas at once, the likelihood of air pockets, and to overcome wiresweep cavities and other imperfections in the final plastic package is reduced.

Abstract: A tube-shaped tray that comprises adjacent compartments for semiconductor devices disposed linearly along the length of the tray. Each compartment consists of a die-shaped bottom container having a supporting structure conforming to the specified geometry of the leads in the formed semiconductor device. A film of protective and lubricating material is provided for placement on top of the device in each compartment, so that a forming tool can freely and safely cooperate with the supporting structure of the die-shaped bottom container to form the leads of the semiconductor device according to the desired specifications. The tray also includes a slidable retaining cover to prevent spillage and damage of the packaged devices.

Abstract: A semiconductor device comprising a semiconductor unit with leads extending therefrom is placed on a bottom packaging tray having a die-shaped upper surface. A top lubricating type film is used over the device 10 and below a punch unit that is used to bend the leads. A process of assembling the semiconductor device on a die type package is disclosed which includes placing the semiconductor device with leads on a packaging tray with upper lead-shaped baring surfaces, placing an anti-friction film sheet over the tray and over the device with its leads extending therefrom, and actuating a punch unit disposed above the film sheet, thereby forming or bending the leads and simultaneously using the die type tray for packaging the semiconductor device.

Abstract: An apparatus and method for precisely positioning an integrated circuit lead frame is disclosed. This apparatus includes a positioning post that cooperates with an index hole in the lead frame, and a lower spring finger. The index hole of the lead frame is placed over the positioning post, and the opposite or bottom side of the lead frame rests on the lower spring finger. An upper spring finger is then brought down on top of the lead frame, aligning with the lower spring finger. As the two spring fingers press against the lead frame, the deflection of the two spring fingers cause the lead frame to move slightly and causes the positioning post located in the index hole to function as a mechanical stop of the deflection movement of the lead frame thereby achieving a very accurate positioning of the lead frame.

Abstract: A lead frame cutting apparatus for various sized integrated circuit packages and method therefor is disclosed. This apparatus employs punches in conjunction with a thin L-shaped cutting plate, which is also symmetrical, allowing both sides to be used. This thin cutting plate is fabricated as one of a plurality of thin cutting plates using a relatively inexpensive single cutting process that cuts all the thin cutting plates in one cutting operation thereby saving money and time compared to the machined, thick cutting plate of the prior art. The L-shape of the cutting plate and the use of the associated punches allows integrated circuit packages of different sizes to be processed with the apparatus of the present invention using a two-pass approach. The integrated circuit package is positioned correctly on the L-shaped cutting plate, and the punches perform the cutting function on two of the four sides of the lead frame.