摘要:
Methods of making integrated circuit device packages and substrates for making the packages are disclosed. An embodiment of a method of making a substrate includes providing an unpatterned sheet of polyimide material having a first surface and an opposite second surface. A planar metal layer is attached to the second surface of the polyimide sheet. The metal layer is patterned to form an array of package sites, with each site including a planar die pad and planar leads. Apertures are formed through the polyimide sheet, either before or after attaching the metal layer. Each aperture is juxtaposed with a lead allowing access thereto. A method of making a package using the substrate includes mounting an integrated circuit device above the die pad (e.g., on the substrate or on the die pad through an aperture in the substrate). Bond wires are connected between the integrated circuit device and the leads through the apertures. An insulative encapsulant is applied so as to cover the integrated circuit device and fill the apertures. A method of making multiple packages includes a final step of cutting an encapsulated array of package sites with a saw to separate individual packages.
摘要:
The invention discloses a method of making solder ball mounting pads on a substrate that have better ball shear performance, ball thermal cycle reliability, ball attach yield, and ball positional tolerances, than the solder ball mounting pads of the prior art. The method includes providing a sheet of material having a layer of metal thereon, and patterning the layer to define a solder ball mounting pad therein. The pad includes a central pad having at least two spokes radiating outward from it. An insulative mask is formed over the metal layer, and an opening is formed in the mask such that the central pad and an inner portion of each of the spokes is exposed therethrough, and an outer portion of each of the spokes is covered by the mask. In one embodiment, the central pad, spokes, and opening in the mask are shaped and arranged with respect to each other such that the pad and exposed portion of the spokes form a radially symmetrical pattern within the opening.
摘要:
A plastic leaded semiconductor package (20) has a semiconductor device (614) encapsulated in the package and mounted to a lead frame (612). The lead frame has a plurality of leads (622) that extend beyond the body (610) of the encapsulated package. Each of the plurality of leads is made from a metal having a predetermined coefficient of thermal expansion. A second metal (627) with a different coefficient of thermal expansion is disposed on at least one portion of each of the leads.
摘要:
A high performance integrated circuit chip package includes a support substrate having conductors extending from one face to the opposite face thereof and a multilayer wiring substrate on the opposite face of the support substrate for connecting chips mounted thereon to one another and to the conductors. A heat sink includes microchannels at one face thereof, with thermally conductive cushions connecting the one face of the heat sink with the exposed back sides of the chips, to provide a high density chip package with high heat dissipation. The support substrate and heat sink may be formed of blocks of material having thermal expansion matching silicon. The cushions are a low melting point solder, preferably pure indium, and are sufficiently thick to absorb thermal stresses, but sufficiently thin to efficiently conduct heat from the chips to the heat sink.