Abstract: A digital computer includes a processor, a memory and a program which operate in combination for inputting a placement of cells for an integrated circuit chip, and a netlist of wiring nets interconnecting the cells. The placement is divided into a plurality of contiguous regions, and cell densities in the regions are computed in accordance with locations of the cells in the placement. Wiring densities in the regions are computed in accordance with the locations of the cells and the netlist. The shapes of the regions are altered to produce altered regions such that cell densities and wiring densities in the altered regions are more level or uniform. The placement is then altered such that the cells occupy locations in the altered regions which are relative to their locations in the original regions. The porosities of the cells can also be computed and used in the computation of the region shapes.

Abstract: Several inventions are disclosed. A cell architecture using hexagonal shaped cells is disclosed. The architecture is not limited to hexagonal shaped cells. Cells may be defined by clusters of two or more hexagons, by triangles, by parallelograms, and by other polygons enabling a variety of cell shapes to be accommodated. Polydirectional non-orthogonal three layer metal routing is disclosed. The architecture may be combined with the tri-directional routing for a particularly advantageous design. In the tri-directional routing arrangement, electrical conductors for interconnecting terminals of microelectronic cells of an integrated circuit preferably extend in three directions that are angularly displaced from each other by 60.degree.. The conductors that extend in the three directions are preferably formed in three different layers. A method of minimizing wire length in a semiconductor device is disclosed. A method of minimizing intermetal capacitance in a semiconductor device is disclosed.

Abstract: Several inventions are disclosed. A cell architecture using hexagonal shaped cells is disclosed. The architecture is not limited to hexagonal shaped cells. Cells may be defined by clusters of two or more hexagons, by triangles, by parallelograms, and by other polygons enabling a variety of cell shapes to be accommodated. Polydirectional non-orthogonal three layer metal routing is disclosed. The architecture may be combined with the tri-directional routing for a particularly advantageous design. In the tri-directional routing arraingement, electrical conductors for interconnecting terminals of microelectronic cells of an integrated circuit preferrably extend in three directions that are angularly displaced from each other by 60.degree.. The conductors that extend in the three directions are preferrably formed in three different layers. A method of minimizing wire length in a semiconductor device is disclosed. A method of minimizing intermetal capacitance in a semiconductor device is disclosed.

Abstract: A cell architecture using hexagonal shaped cells is disclosed. The architecture is not limited to hexagonal shaped cells. Cells may be defined by clusters of two or more hexagons, by triangles, by parallelograms, and by other polygons enabling a variety of cell shapes to be accommodated. Polydirectional non-orthogonal three layer metal routing is disclosed. The architecture may be combined with the tri-directional routing for a particularly advantageous design. In the tri-directional routing arraingement, electrical conductors for interconnecting terminals of microelectronic cells of an integrated circuit preferrably extend in three directions that are angularly displaced from each other by 60.degree.. The conductors that extend in the three directions are preferrably formed in three different layers. A method of minimizing wire length in a semiconductor device is disclosed. A method of minimizing intermetal capacitance in a semiconductor device is disclosed. A novel device called a "tri-ister" is disclosed.

Abstract: Several inventions are disclosed. A cell architecture using hexagonal shaped cells is disclosed. The architecture is not limited to hexagonal shaped cells. Cells may be defined by clusters of two or more hexagons, by triangles, by parallelograms, and by other polygons enabling a variety of cell shapes to be accommodated. Polydirectional non-orthogonal three layer metal routing is disclosed. The architecture may be combined with the tri-directional routing for a particularly advantageous design. In the tri-directional routing arraingement, electrical conductors for interconnecting terminals of microelectronic cells of an integrated circuit preferrably extend in three directions that are angularly displaced from each other by 60.degree.. The conductors that extend in the three directions are preferrably formed in three different layers. A method of minimizing wire length in a semiconductor device is disclosed. A method of minimizing intermetal capacitance in a semiconductor device is disclosed.

Abstract: Several inventions are disclosed. A cell architecture using hexagonal shaped cells is disclosed. The architecture is not limited to hexagonal shaped cells. Cells may be defined by clusters of two or more hexagons, by triangles, by parallelograms, and by other polygons enabling a variety of cell shapes to be accommodated. Polydirectional non-orthogonal three layer metal routing is disclosed. The architecture may be combined with the tri-directional routing for a particularly advantageous design. In the tri-directional routing arraingement, electrical conductors for interconnecting terminals of microelectronic cells of an integrated circuit preferrably extend in three directions that are angularly displaced from each other by 60.degree.. The conductors that extend in the three directions are preferrably formed in three different layers. A method of minimizing wire length in a semiconductor device is disclosed. A method of minimizing intermetal capacitance in a semiconductor device is disclosed.

Abstract: A process for designing an integrated circuit chip s comprises specifying a plurality of regions on the chip in which a plurality of objects are to be placed, such that there are more of the objects than the regions, and specifying penalties for the objects to be placed in the regions respectively. The objects can be microelectronic cells, interconnect wiring segments, etc. An assignment of the objects to the regions is constructed, and a number of objects for movement between the regions is selected. An optimal permutation of movement of the selected number of objects between the regions is computed such that a cost corresponding to the total penalties for the assignment is maximally reduced, and the assignment is modified by moving the selected number of objects through the optimal permutation. The process steps are repeated iteratively such that a maximum number of objects which will produce a maximal reduction in cost is moved during each iteration.

Abstract: Several inventions are disclosed. A cell architecture using hexagonal shaped cells is disclose. The architecture is not limited to hexagonal shaped cells. Cells may be defined by clusters of two or more hexagons by triangles, by parallelograms, and by other polygons enabling a variety of cell shapes to be accommodated. Polydirectional non-orthogonal three layer metal routing is disclosed. The architecture may be combined with the tri-directional routing for a particularly advantageous design. In the tri-directional routing arraingement, electrical conductors for interconnecting terminals of microelectronic cells of an integrated circuit preferrably extend in three directions that are angularly displaced from each other by 60.degree.. The conductors that extend in the three directions are preferrably formed in three different layers. A method of minimizing wire length in a semiconductor device is disclosed. A method of minimizing intermetal capacitance in a semiconductor device is disclosed.

Abstract: Several inventions are disclosed. A cell architecture using hexagonal shaped cells is disclosed. The architecture is not limited to hexagonal shaped cells. Cells may be defined by clusters of two or more hexagons, by triangles, by parallelograms, and by other polygons enabling a variety of cell shapes to be accommodated. Polydirectional non-orthogonal three layer metal routing is disclosed. The architecture may be combined with the tri-directional routing for a particularly advantageous design. In the tri-directional routing arraingement, electrical conductors for interconnecting terminals of microelectronic cells of an integrated circuit preferrably extend in three directions that are angularly displaced from each other by 60.degree.. The conductors that extend in the three directions are preferrably formed in three different layers. A method of minimizing wire length in a semiconductor device is disclosed. A method of minimizing intermetal capacitance in a semiconductor device is disclosed.

Abstract: A computer implemented method for generating and placing clusters of cells for integrated circuit design includes providing a netlist including cells, and nets of wires interconnecting the cells. A metric is specified for measuring distance between cells as a function of netlist interconnections. A length of a net is the number of cells interconnected by said net minus one, and a distance between two cells is a sum of lengths of nets that provide a shortest path between the cells. A maximum cluster size criterion, such as maximum distance of a cell from the center of a cluster, is specified to provide a desired amount of overlap between clusters. Clusters of cells are generated, each cluster being generated by designating one of the cells as the center, processing the netlist using the metric to determine distances of cells from the center, and assigning cells having progressively increasing distances from the center to the cluster until the maximum cluster size criterion is reached.

Abstract: A process for designing an integrated circuit chip includes specifying a set of cells, a set of wiring nets for interconnecting the cells, and a set of regions on the chip in which the cells are to be placed. An assignment of the cells of the set to the regions is generated, and the set of cells is randomly divided into a first subset of cells which remain in the assignment, and a second subset of cells which are removed from the assignment. Penalties are computed for assigning the cells of the second subset to the regions respectively, and the cells of the second subset are assigned to the regions such that a total penalty thereof is minimized. The process is repeated iteratively with the size of the second subset being progressively reduced relative to the size of the first subset until an end criterion is reached.

Abstract: A method of producing a placement of cells for a microelectronic integrated circuit in accordance with specified cell interconnects includes constructing a hierarchial cluster tree based on the interconnects in which a lowest level of the tree includes clusters of interconnected cells, and each successively higher level includes clusters of interconnected clusters from a successively lower level. Clusters in each level are merged by a min-cut operation. Clusters of each successively lower level are then placed within clusters of each successively higher level in progressively decreasing order of levels. Clusters are placed in each level by computing a current gravity point for each cluster in accordance with the cells therein, computing a new gravity point for each cluster in accordance with the current gravity points and the interconnects, and moving each cluster from the current gravity point to the new gravity point.

Abstract: A microelectronic integrated circuit includes a semiconductor substrate, and a plurality of microelectronic devices formed on the substrate. Each device has a periphery defined by a triangle, and includes an active area formed within the periphery, a central terminal formed in a central portion of the active area, and interconnected first to third terminals formed in the active area adjacent to vertices of the triangle respectively. First to third gates are formed between the first to third terminals respectively and the central terminal, and have contacts formed outside the active area adjacent to the sides of the triangle. The power supply connections to the central terminal and the first to third terminals, the conductivity type (NMOS or PMOS), and the addition of a pull-up or a pull-down resistor is selected for each device to provide a desired OR, NOR, AND or NAND function.

Abstract: A microelectronic integrated circuit includes a semiconductor substrate, and a plurality of CMOS microelectronic devices formed on the substrate. Each device includes a triangular ANY element of a first conductivity type (PMOS or NMOS), and a triangular ALL element of a second conductivity type (NMOS or PMOS), the ANY and ALL elements each having a plurality of inputs and an output that are electrically interconnected respectively. The ANY element is basically an OR element, and the ALL element is basically an AND element. However, the power supply connections and the selection of conductivity type (NMOS or PMOS) for the ANY and ALL elements can be varied to provide the device as having a desired NAND, AND, NOR or OR configuration, in which the ANY element acts as a pull-up and the ALL element acts as a pull-down, or vice-versa.

Abstract: A microelectronic integrated circuit includes a semiconductor substrate, and a plurality of microelectronic devices formed on the substrate. Each device has a periphery defined by a triangle, and includes an active area formed within the periphery. First and second terminals are formed in the active area adjacent to two vertices of the triangle respectively, and first to third gates are formed between the first and second terminals. The gates have contacts formed outside the active area adjacent to a side of the triangle between the two vertices. The power supply connections to the first and second terminals, the conductivity type (NMOS or PMOS), and the addition of a pull-up or a pull-down resistor are selected for each device to provide a desired AND, NAND, OR or NOR function. A third terminal can be formed between two of the gates and used as an output terminal to provide an AND/OR logic function. The devices are interconnected using three direction routing based on hexagonal geometry.

Abstract: Electrical conductors for interconnecting terminals of microelectronic cells of an integrated circuit extend in three directions that are angularly displaced from each other by 60.degree.. The conductors pass through points defined by centers of closely packed hexagons superimposed on the circuit such that the conductors extend perpendicular to edges of the hexagons. The conductors that extend in the three directions can be formed in three different layers, or alternatively the conductors that extend in two or three of the directions can be formed in a single layer as long as they do not cross. The conductors can be formed in layers that are electrically insulated from the cells and extend over the cells, or can extend through hexagons between cells. Cells are defined by clusters of two or more hexagons, enabling a variety of cell shapes to be accommodated.