Abstract: A leadframe with a base metal structure (for example, copper) and first and second surfaces. A first metal layer, which is adhesive to polymeric materials such as molding compounds, is adherent to the first leadframe surface. The second leadframe surface is covered by a second metal layer for affinity to reflow metals such as tin alloy; this second metal layer has a different composition from the first metal layer. One example of the first surface is a nickel layer (201) in contact with the base metal (105), a palladium layer (202) in contact with the nickel layer, and an outermost tin layer (203) in contact with the palladium. Another example is an oxidized surface of the base metal. The second metal layer, on the second leadframe surface, comprises a nickel layer (201) in contact with the base metal (105), a palladium layer (202) in contact with the nickel layer, and an outermost gold layer (204) in contact with the palladium layer.

Abstract: A semiconductor device having a leadframe comprised of a base metal (110, e.g., copper), a chip mount pad (103) and a plurality of lead segments (104). Each of the segments has a first end (104a) near the mount pad and a second end (104b) remote from the mount pad. The device further has a semiconductor chip (103) attached to the mount pad and electrical interconnections (107) between the chip and the first segment ends. Encapsulation material (120) covers the chip, the bonding wires and the first segment ends, yet leaves the second segment ends exposed. At least portions of the second segment ends have the base metal covered by a layer of solderable metal (130, e.g., nickel) and by an outermost layer of noble metal (140, e.g., stack of palladium and gold).

Abstract: A heatsink architecture employing a combination of stiffeners and flex substrate to improve the sinking of heat from the integrated circuit. The stiffener may be employed in numerous locations, including above the integrated circuit, or interposed between the integrated circuit and an e-block. The flex substrate may be interposed between the integrated circuit and the stiffener, while in other embodiments the integrated circuit is directly coupled to the e-block via heat conductive epoxy and the like. Solder balls may be employed to connect the flex substrate to integrated circuit. The flex substrate may take different forms, and may or may not be connected to the e-block. The flex substrate may be connected directly to the e-block, or connected via an e-pin extending through layers including the flex substrate and/or the stiffener.

Abstract: A method for completing an assembled semiconductor device, which has metallic leads for connection to external parts. The method comprises the step (202) of encapsulating the assembled device with a polymeric precursor so that at least portions of the leads remain un-encapsulated. Without significant delay, these un-encapsulated lead portions are plated (203) with at least one metal layer suitable for connection to external parts; the plating step has no noticeable impact on the uncured mold compound. The encapsulated and plated device is then submitted (204) to a sequence of elevated temperatures for specified periods of time so that concurrently the precursor is polymerized and the at least one metal layer is annealed.

Abstract: An apparatus consisting of a leadframe (301) and a metallic heat spreader (310). The leadframe, made of a planar metal sheet, includes a plurality of non-coplanar members (312) operable as mechanical couplers configured to grip inserted objects. The heat spreader has a central pad (310) suitable for mounting a heat-generating object, and a plurality of handles (312) in locations to match the members; the handles are coupled with the members. One member end is formed as a clamp having projections from the planar sheet, operable to grip one of the handles, when it is inserted into the coupler, and also has a bend so that the plane of the heat spreader, after insertion of its handles into the clamps, is spaced from the plane of the leadframe. A gap is thus created between the spreader and the first leadframe segment ends.

Abstract: A leadframe with a base metal structure (for example, copper) and first and second surfaces. A first metal layer, which is adhesive to polymeric materials such as molding compounds, is adherent to the first leadframe surface. The second leadframe surface is covered by a second metal layer for affinity to reflow metals such as tin alloy; this second metal layer has a different composition from the first metal layer. One example of the first surface is a nickel layer (201) in contact with the base metal (105), a palladium layer (202) in contact with the nickel layer, and an outermost tin layer (203) in contact with the palladium. Another example is an oxidized surface of the base metal. The second metal layer, on the second leadframe surface, comprises a nickel layer (201) in contact with the base metal (105), a palladium layer (202) in contact with the nickel layer, and an outermost gold layer (204) in contact with the palladium layer.

Abstract: A semiconductor device having a leadframe comprised of a base metal (110, e.g., copper), a chip mount pad (103) and a plurality of lead segments (104). Each of the segments has a first end (104a) near the mount pad and a second end (104b) remote from the mount pad. The device further has a semiconductor chip (103) attached to the mount pad and electrical interconnections (107) between the chip and the first segment ends. Encapsulation material (120) covers the chip, the bonding wires and the first segment ends, yet leaves the second segment ends exposed. At least portions of the second segment ends have the base metal covered by a layer of solderable metal (130, e.g., nickel) and by an outermost layer of noble metal (140, e.g., stack of palladium and gold).

Abstract: A semiconductor chip having a planar active surface including an integrated circuit protected by an inorganic overcoat; the circuit has metallization patterns including a plurality of contact pads. Each of these contact pads has an added conductive layer on the circuit metallization. This added layer has a conformal surface adjacent the chip, including peripheral portions of the overcoat, and a planar outer surface; this outer surface is suitable to form metallurgical bonds without melting. The chip contact pads may have a distribution arrayed in the center of the chip in close proximity to the chip neutral line; the distribution may leave an area portion of the active chip surface available for attaching a thermally conductive plate. The chip may further have a non-conductive adhesive layer over the overcoat, filling the spaces between the added conductive layers on each contact pad.

Abstract: A semiconductor chip having a planar active surface including an integrated circuit; the circuit has metallization patterns including a plurality of contact pads. Each of these contact pads has an added conductive layer on the circuit metallization. This added layer has a conformal surface adjacent the chip and a planar outer surface, and this outer surface is suitable to form metallurgical bonds without melting. The chip contact pads may have a distribution such that an area portion of the active chip surface is available for attaching a thermally conductive plate; this plate has a thickness compatible with the thickness of the conductive pad layer.