Abstract: An efficient technique or providing ROM memory on a microprocessor local bus is described whereby a ROM and all necessary address decoding and control circuitry is incorporated in a single integrated circuit. By doing this, only one chip is required to add ROM to a microprocessor local bus, saving considerable space and power over discrete implementations. The ROM is implemented in a wide memory format, matching the bus width of the microprocessor to which it is connected. This permits full-speed access to the local bus ROM, and eliminates any need for such techniques as ROM "shadowing".

Abstract: The present invention provides a method for fabricating an integrated circuit package, as well the resulting integrated circuit package, which retains a heatsink in close communication with a mold cavity. This precludes any encapsulant from flowing between the heatsink and the inner surface of a mold cavity. As a consequence, the bottom of the heatsink is not encapsulated and is thus exposed. This is accomplished by including posts, attached to the leadframe assembly, which have the function of exerting a downward force on a leadframe assembly and, in turn, on the heatsink. Tie bars, which are non-functional parts of a leadframe assembly, can be utilized as posts by bending the posts into an upright position.

Abstract: A semiconductor die having raised conductive bumps on its surface for connecting to other devices or systems is disposed on a face of a preformed planar structure (interposer) having through holes. Solder joints with conductive bumps on an underlying substrate are formed in the through holes. In one embodiment, the interposer is dissolvable. In another embodiment, the through holes are at least partially filled with a conductive material for electrically connecting to the die. In another embodiment, the through holes are angled so that the interposer acts as a pitch spreader or adapter. In another embodiment, ball bumps are disposed on a side of the interposer away from the die. Various other embodiments are directed to multi-tier flip-chip arrays employing preformed planar structures between tiers.

Abstract: A technique for reducing thermally-induced mechanical stresses on bond pads in semiconductor device assemblies is accomplished by grouping (laying out) the bond pads in two parallel rows, approximately centered about a central axis of the die. Further, the bond pads of one row are axially offset from the bond pads of the other row, thereby forming a two-row zig-zag linear configuration of bond pads. The "axis" is a line preferably passing through a thermal centroid of the die. By keeping the bond pad layout close to the axis, lateral thermally-induced displacements of the bond pads relative to the axis can be minimized and controlled. Longitudinal (axial) displacements of the bond pads are accommodated by flexing, rather than compression, of conductive lines (such as leadframe fingers) connecting to the bond pads and entering the die perpendicular to the axis.

Abstract: The present invention is an improved method and apparatus for selecting and replacing a block of a set of cache memory. The present invention provides for the weighted random replacement of blocks of cache memory by assigning indices to the memory blocks of a given set of cache memory. One of the assigned indices is then randomly selected by the present invention. The memory block of the given set to which the randomly selected index is assigned is replaced. The indices are assigned such that one or more blocks of the given set of cache memory have a high probability of replacement, whereas the other blocks of the given set of cache memory have significantly lower probabilities of replacement.

Abstract: Composite bond pad structure and geometry increases bond pad density and reduces lift-off problems. Bond pad density is increased by laying out certain non-square bond pads which are shaped, sized and oriented such that each bond pad closely conforms to the shape of the contact footprint made therewith by a bond wire or lead frame lead and aligns to the approach angle of the conductive line to which it is connected. Alternating, interleaved, complementary wedge-shaped bond pads are discussed. Bond pad liftoff is reduced by providing an upper bond pad, a lower bond pad and an insulating component between the upper and lower bond pads. At least one opening is provided through the insulating component, extending from the bottom bond pad to the upper bond pad. The at least one opening is aligned with a peripheral region of the bottom bond pad and is filled with conductive material.

Abstract: An apparatus and method for mounting and connecting a plurality of integrated circuit chip dice to a printed circuit substrate by means of a small circuit board (such as a Mini-Board) that may be adapted to attach and connect into a plurality of different types of printed circuit board systems. A pattern of conductors that monotonically increases in pitch and width from a central point on a planar structure to the perimeter edge of the structure allows matching of any type of printed circuit board connections. A standard Mini-Board may be fabricated and tested before attaching to an electronic system printed circuit board. Repair and rework is easily facilitated with a minimum amount of damage to a printed circuit board by utilizing the present invention. A plurality of active and passive electronic components may also be attached and connected to the planar structure of the present invention. A hybrid mini-system may be fabricated and tested before connecting it into a system printed circuit board.

Abstract: A free running relaxation oscillator is disposed on a semiconductor integrated circuit die for generating a frequency representative of the natural frequency of the die. The natural frequency of the die changes for different operating temperatures and voltages. An optimal speed may be determined at which the die will reliably operate by measuring the natural frequency. The die may be effectively graded and matched with a similar die by correlating the natural frequency of the die with the temperature and voltage values at which the natural frequency was measured for each die. A plurality of integrated circuit dice may be connected into a digital system, and the natural frequencies of each die may be monitored so as to optimize the system operating speed, reduce system power consumption without degrading performance, and/or increase the operating speed of a slower die by changing the temperature and/or operating voltage thereof.

Abstract: In cases where there are at least some large gaps between edges of a semiconductor die and the inner ends of package conductors defining a die-receiving area, one or more bond wire support structure are disposed in the gap, thereby causing a long bond wire to behave as two or more shorter bond wires. The bond wires are tacked to a top surface of the support structure by various alternative means. Alternatively, a "jumper" structure having conductive traces of graduated length can be disposed in the die-receiving area between the die and the edges of the die-receiving area, providing an intermediate connection between the die and the leads of the package, thereby permitting short bond wires to be used in lieu of long bond wires.

Abstract: Positive mechanical alignment is provided between substrates using micro-bump contacts by forming "detented" conductive bump contacts on one substrate having a concave end which receive and align the generally convex contour of bump contacts on the other substrate. Various configurations of concavities and convexities are described. Flux may be disposed in the concave end of the detented bump contact to promote formation of joints between the concave and convex bump contacts. Both bump contacts may be formed of reflowable material, such as solder, or one or the other of the contacts may be formed of a non-reflowable material which may also function as a standoff between the two substrates. Each substrate is provided with a plurality of bump contacts, and one substrate may be provided with a combination of convex and concave bump contacts corresponding to concave and convex bump contacts on the other substrate. The inventive technique is useful for joining die-to-die, die-to-substrate, or package-to-substrate.

Abstract: A technique for providing partially and fully overmolded semiconductor packages is described which prevents delamination (detachment) of the molding compound from the substrate by allowing the molding compound to flow through holes in the substrate and forming it into rivet-like anchors on the opposite side of the substrate. Various shapes of rivet-like anchors are described. Different embodiments provide for the formation of molded standoffs and locating pins integral to the anchor structures.

Abstract: Plastic (or resinous) materials used to package (or support) electronic devices typically have thermal coefficients of expansion exceeding that of the device to be packaged. A "loading" material (agent) having a coefficient of expansion significantly less than the "base" plastic material (molding compound), less than that of the die, and preferably zero or negative over a temperature range of interest, is mixed with the "base" plastic material to produce a plastic molding compound with a lower overall thermal coefficient of expansion. Titanium dioxide, zirconium oxide and silicon are discussed as loading agents. The loading material is mixed into the plastic molding compound in sufficient quantity to ensure that the resulting mixture exhibits an overall thermal coefficient of expansion that is more closely matched to that of the electronic device.

Abstract: The present invention relates to a system and method for control and delivery of radio frequency power in plasma process systems. The present invention monitors the power, voltage, current, phase, impedance, harmonic content and direct current bias of the radio frequency energy being delivered to the plasma chamber. In addition, the plasma mode of operation may be controlled by creating either a capacitively or inductively biased radio frequency source impedance. A radio frequency circulator prevents reflected power from the plasma chamber electrode to damage the power source and it further dissipates the reflected power in a termination resistor. The termination resistor connected to the circulator also effectively terminates harmonic energy caused by the plasma non-linearities. Multiple plasma chamber electrodes and radio frequency power sources may be similarly controlled.

Abstract: A process for manufacturing substrate including a non-conductive support layer and a plurality "n" of conductive leads disposed on the support layer. The leads are arranged in a generally radial pattern about a central point on the support layer, each of the leads having a width "w" and spaced a distance "d" from one another at their innermost ends, thereby forming a generally square opening of side dimension "s". The substrate accommodates semiconductor dies ranging in size from smaller than the opening, to approximately equal to that of the opening, to substantially larger than the opening, such as four times the size (linear dimension) of the opening. The die is bonded to the substrate. Other elements of a semiconductor device assembly are added to the resulting structure.

Abstract: A semiconductor device assembly having external connections, including power supply connections such as to a power source or ground, is made without resort to bond fingers. Rather, external connections are directly made from a semiconductor die to a conductive layer. The conductive layer is disposed on one surface of a printed wring board and is divided into electrically insulated conductive segments. Each of the conductive segments is connected to an external connection, and includes one or more interconnects that can be directly connected to a semiconductor die. The conductive segments are surrounded by an array of bond fingers which serve to connect the semiconductor die to further external connections, such as signal connections. The present invention is especially advantageous in the fabrication of pin grid array (PGA) and ball grid array (BGA) type integrated circuit packages.

Abstract: An engine which employs a cam follower mechanism to reduce wear and reduce the size of an assembled engine. The cam follower mechanism utilizes guide rails located to reduce side thrust on the valve stem. The engine employs a high speed quill shaft to synchronize independent cam shafts existing in each of a plurality of interconnected engines. The engine is assembled using a single size fastener to provide a uniform stress gradient within the engine. The engines are interconnected utilizing O-ring seals. The engine provides a piston crown utilizing a connecting rod directly connected to the bottom surface of the piston crown. The piston crown is stabilized along the longitudinal cylinder axis by a rail guide. Connecting rods are provided which require less than one hundred eighty degrees (180.degree.) circumference of a crankshaft pin for support so that a plurality of connecting rods can be associated with a single crankshaft pin.

Abstract: Via filling is enhanced by the techniques of 1) providing pillars immediately underneath semiconductor features, such as metal layer contacts (inter-connection points), and 2) polishing off excess via-filling material so that the via-filling plug is flush with the topmost insulating layer. The pillars are provided under every feature over which a via will be formed, so that an insulating layer surrounding the via will be thinner at the location of the feature. If necessary, polishing is continued to thin the insulating layer so that the plugs in initially selectively under-filled vias are made flush with the insulating layer. Method and apparatus are disclosed.

Abstract: A technique for integrated circuit floorplanning using irregularly shaped dies (e.g., triangular, elongated rectangular, parallelogram-shaped, etc.) is described whereby the layout of the integrated circuit die is accomplished by partitioning (slicing) the die into progressively smaller groups of more than two areas into which functions (active elements, or circuits) are assigned according to their area requirements. The die is iteratively sub-partitioned.

Abstract: The present invention provides a method for fabricating an integrated circuit package, as well the resulting integrated circuit package, which retains a heatsink in close communication with a mold cavity. This precludes any encapsulant from flowing between the heatsink and the inner surface of a mold cavity. As a consequence, the bottom of the heatsink is not encapsulated and is thus exposed. This is accomplished by including posts, attached to the leadframe assembly, which have the function of exerting a downward force on a leadframe assembly and, in turn, on the heatsink. Tie bars, which are non-functional parts of a leadframe assembly, can be utilized as posts by bending the posts into an upright position.

Abstract: A method and apparatus for testing semiconductor devices at device operating speed for both proper combinational and timing logic functions with a standard low speed logic tester. A high speed phase-lock-loop system clock of the semiconductor device is frequency and phase locked to the lower speed logic tester clock. Test data is shifted into the semiconductor device at the test clock speed. Two controlled system clock pulses are utilized to clock the test data into the semiconductor devices. The first of these two pulses starts the test and the second ends the test. In this way, the combinational functions of the semiconductor devices are tested at the system operating speed.