Abstract:
Methods of independently migrating a hierarchical design are disclosed. A method for migrating a macro in an integrated circuit comprises: determining an interface strategy between a base cell in the macro and the macro, the base cell including an interface element involved in the interface strategy; migrating the base cell independently with respect to the macro based on the interface strategy; initially scaling the macro; swapping the migrated base cell into the macro; and legalizing content of the initially scaled macro.
Abstract:
Disclosed is a method that predicts test yield for a semiconductor product, prior to design layout. This is accomplished by applying a critical area analysis to individual library elements that are used to form a specific product and by estimating the test yield impact of combining these library elements. For example, the method considers the test yield impact of sensitivity to library element to library element shorts and the test yield impact of sensitivity to wiring faults. The disclosed method further allows die size growth to be traded off against the use of library elements with higher test yield in order to provide an optimal design solution. Thus, the method may be used to modify library element selection so as to optimize test yield. Lastly, the method further repeats itself at key design checkpoints to revalidate initial test yield (and cost) assumptions made when the product was quoted to a customer. Thus, the method provides increased accuracy of test yield estimate from initial sizing through design and further allows designs to be modified to improve test yield.
Abstract:
A method, apparatus, and computer program product for visually indicating the interaction between one or more edges of a design that contribute to a defined critical area pattern.
Abstract:
An integrated circuit including a first wire of a first level of wiring tracks, a second wire of a second level of wiring tracks, a third wire of a third level of wiring tracks, and a fourth wire located a first distance from the second wire in the second level of wiring tracks. A first via connects the first and second wires at a first location of the second wire. A second via connects the second and third wires at the first location, the second via is substantially axially aligned with the first via. A third via connecting the third and fourth wires at a second location of the fourth wire. A fourth via connecting the first and fourth wires at the second location, the fourth via is substantially axially aligned with the third via. The second, third, and fourth vias, and the third and Fourth wires form a path between the first and second wires redundant to the first via.
Abstract:
A system, method and program product for predicting yield of a VLSI design. A method is provided including the steps of: identifying and grouping sub-circuits contained within an integrated circuit design by type; calculating critical area values for regions within the integrated circuit design; and applying different yield models to critical area values based on the types of the regions used to calculate the critical area values, wherein each yield model is dependent on a type.
Abstract:
Disclosed is a method and system for inserting redundant paths into an integrated circuit. Particularly, the invention provides a method for identifying a single via in a first path connecting two elements, determining if an alternate route is available for connecting the two elements (other than a redundant via), and for inserting a second path into the available alternate route. The combination of the first and second paths provides greater redundancy than inserting a redundant via alone. More importantly, such redundant paths provide for redundancy when congestion prevents a redundant via from being inserted adjacent to the single via. An embodiment of the method further comprises removing the single via and any redundant wire segments, if all of the additional vias used to form the second path can be made redundant.
Abstract:
A method, system and program product for migrating an integrated circuit (IC) design from a source technology without radical design restrictions (RDR) to a target technology with RDR, are disclosed. The invention implements a minimum layout perturbation approach that addresses the RDR requirements. The invention also solves the problem of inserting dummy shapes where required, and extending the lengths of the critical shapes and/or the dummy shapes to meet ‘edge coverage’ requirements.
Abstract:
The invention provides a method and structure for optimizing placement of redundant vias within an integrated circuit design. The invention first locates target vias by determining which vias do not have a redundant via. Then, the invention draws marker shapes on or adjacent to the target vias. The marker shapes are only drawn in a horizontal or vertical direction from each of the target vias. The invention simultaneously expands all of the marker shapes in the first direction to a predetermined length or until the marker shapes reach the limits of a ground rule. During the expanding, different marker shapes will be expanded to different lengths. The invention determines which of the marker shapes were expanded sufficiently to form a valid redundant via to produce a first set of potential redundant vias and the invention eliminates marker shapes that could not be expanded sufficiently to form a valid redundant via.
Abstract:
Methods for modeling a random variable with spatially inhomogenous statistical correlation versus distance, standard deviation, and mean by spatial interpolation with statistical corrections. The method includes assigning statistically independent random variable to a set of seed points in a coordinate frame and defining a plurality of test points at respective spatial locations in the coordinate frame. A equation for a random variable is determined for each of the test points by spatial interpolation from one or more of the random variable assigned to the seed points. The method further includes adjusting the equation of the random variable at each of the test point with respective correction factor equations.
Abstract:
A pixel structure for an image sensor includes a semiconductor material portion having a coplanar and contiguous semiconductor surface and including four photodiodes, four channel regions, and a common floating diffusion region. Each of the four channel regions is directly adjoined to one of the four photodiodes and the common floating diffusion region. The four photodiodes are located within four different quadrants as defined employing a vertical line passing through a point within the common floating diffusion region as a center axis. The common floating diffusion region, a reset gate transistor, a source follower transistor, and a row select transistor are located within four different quadrants as defined employing a vertical line passing through a point within one of the photodiodes as an axis.