Abstract: A method and system for the simultaneous placement of large and small cells in an electronic circuit. A coarse placement using well known methods may provide an initial placement of cells. Cells meeting a size criteria may be selected for further processing. An optimum cell orientation may be determined. An optimum axis of movement for separation may be determined. Overlapping cells may be separated and their positions may be optimized in both horizontal and vertical directions. Any cell moved from its initial placement may be fixed so as not to be moved during subsequent placements. This process may be repeated for cells meeting a new, generally smaller, size criteria. A well known detailed placement process may finalize a design. In this novel manner, large and small cells may be automatically simultaneously placed, deriving speed and quality advantages over prior art methods.

Abstract: A method for manufacturing integrated circuits using opaque field, phase shift masking. One embodiment of the invention includes using a two mask process. The first mask is an opaque-field phase shift mask and the second mask is a single phase structure mask. A phase shift window is aligned with the opaque field using a phase shift overlap area on the opaque field. The phase shift mask primarily defines regions requiring phase shifting. The single phase structure mask primarily defines regions not requiring phase shifting. The single phase structure mask also prevents the erasure of the phase shifting regions and prevents the creation of undesirable artifact regions that would otherwise be created by the phase shift mask.

Abstract: A full phase shifting mask (FPSM) can define substantially all of the features of an integrated circuit using pairs of shifters having opposite phase. In particular, cutting patterns for working with the polysilicon, or gate, layers and active layers of static random access memory (SRAM) cells are considered. To resolve phase conflicts between shifters, one or more cutting patterns can be selected. These cutting patterns include cuts on contact landing pads. This cut simplifies the FPSM layout while ensuring greater critical dimension control of the more important features and reducing mask misalignment sensitivity.

Abstract: Definition of a phase shifting layout from an original layout can be time consuming. If the original layout is divided into useful groups, i.e. clusters that can be independently processed, then the phase shifting process can be performed more rapidly. If the shapes on the layout are enlarged, then the overlapping shapes can be grouped together to identify shapes that should be processed together. For large layouts, growing and grouping the shapes can be time consuming. Therefore, an approach that uses bins can speed up the clustering process, thereby allowing the phase shifting to be performed in parallel on multiple computers. Additional efficiencies result if identical clusters are identified and processing time saved so that repeated clusters of shapes only undergo the computationally expensive phase shifter placement and assignment process a single time.

Abstract: A method and system for enforcing ordering rules for transactions are presented. The method and system generates transaction clump tags for each transaction before the transactions are stored in various type specific transaction queues. A transaction clump tag decoding unit decodes the transaction clump tag to recover temporal information regarding the transaction to avoid violations of the ordering rules.

Abstract: In simulating a physical circuit or system including analog and mixed signal digital-analog components, a computer models the physical circuit or system as a system of simultaneous equations. Conditional equations with associated conditions that can be true or false at different analog solution iterations result in a system of simultaneous equations that can change during the simulation. Rather than reformulating the system of simultaneous equations at each analog solution iteration, the system of simultaneous equations includes slots that are associated with conditional equations as the conditional equations become active. At a given point during the simulation, the conditions associated with the conditional equations are evaluated to determine which conditional equations are active. The values of the active conditional equations are placed in the slots in the system of simultaneous equations. System variables are associated with active conditional equations.

Abstract: Design geometry information from an area outside the area of interest (AOI) on a mask can be combined with inspection information from the AOI to facilitate an accurate, simulated wafer image. The design geometry information can be easily generated or accessed, thereby ensuring an uninterrupted inspection process and minimizing the associated storage costs for the simulation process. The design geometry information can be pseudo design geometry information or actual design geometry information.

Abstract: A low overhead dynamically reconfigurable shared scan-in test architecture is provided. This test architecture advantageously allows for changing scan inputs during the scan operation on a per shift basis. The flexibility of reconfiguring the scan input to scan chain mapping every shift cycle can advantageously reduce both test data volume and test application time.

Abstract: An n-channel metal-insulator-semiconductor field-effect transistor (MISFET) that exhibits a variable threshold voltage is disclosed. The resulting device can be incorporated into a number of useful applications, including as part of a memory device, a logic device, etc.

Abstract: A method of interactively determining at least one optimized design candidate using an optimizer, the optimizer having a generation algorithm and an objective function, the optimized design candidate satisfying a design problem definition, comprises generating design candidates based on the generation algorithm. The generated design candidates are added to a current set of design candidates to form a new set of design candidates. The design candidates are evaluated based on the objective function so that design candidates can be selected for inclusion in a preferred set of design candidates. The current state of the optimizer is presented to a designer for interactive examination and input is received from the designer for updating the current state of the optimizer. These steps are repeated until a stopping criterion is satisfied.

Abstract: A lithography reticle advantageously includes “proximity effect halos” around tight tolerance features. During reticle formation, the tight tolerance features and associated halos can be carefully written and inspected to ensure accuracy while the other portions of the reticle can be written/inspected less stringently for efficiency. A system for creating a reticle data file from an IC layout data file can include a processing module and a graphical display. The processing module can read the IC layout data file, identify critical features and define a halo region around each of the critical features. The graphical user interface can facilitate user input and control. The system can be coupled to a remote IC layout database through a LAN or a WAN.

Abstract: A method and system of optimizing exceptions to default timing constraints for use in integrated circuit design tools is described. A list of exceptions is accessed and optimized to generate a new list of exceptions. Optimizations may include: elimination of redundant information, resolution of conflicting information, and other transformations. The new list allows more efficient timing analysis, synthesis, placement, routing, noise analysis, power analysis, reliability analysis, and other operations to be performed by EDA tools.

Abstract: The present invention, generally speaking, provides a placement method for the physical design of integrated circuits in which natural topological feature clusters (topo-clusters) are discovered and exploited during the placement process. Topo-clusters may be formed based on various criteria including, for example, functional similarity, proximity (in terms of number of nets), and genus. Genus refers to a representation of a netlist in terms of a number of planar netlists—netlists in which no crossing of nets occurs. Topo-clusters drive initial placement, with all of the gates of a topo-cluster being placed initially in a single bin of the placement layout or within a group of positionally-related bins. The portion of a topo-cluster placed within a given bin is called a quanto-cluster. An iterative placement refinement process then follows, using a technique referred to herein as Geometrically-Bounded FM (GBFM), and in particular Dual GBFM.

Abstract: In the simulation of an analog and mixed-signal analog-digital physical circuit, events are assigned scheduled times. The events are stored in buckets in a hash table, with the scheduled times of the events in each bucket associated with the bucket. The scheduled times are organized into a heap, with the earliest scheduled time at the root of the heap. The earliest scheduled time is removed from the heap, and the events in the associated bucket are performed. Performing the scheduled events can cause new events to be scheduled, and existing events to be de-scheduled. When all the events in the bucket associated with the earliest scheduled time are simulated, the remaining scheduled times are re-organized into a new heap, and the steps of removing the earliest scheduled time, performing the scheduled events, and re-organizing the remaining scheduled times are repeated.

Abstract: A method and system for constructing a structural model of a memory for use in ATPG (Automatic Test Pattern Generation). According to an embodiment of the present invention, behavioral models of memories of the simulation libraries are re-coded into simplified behavioral models using behavioral hardware description language (e.g., Verilog). Then, the simplified behavioral models are automatically converted into structural models that include ATPG memory primitives. The structural models are then stored for subsequent access during pattern generation. In one embodiment, for modeling random access memories (RAMs), the ATPG memory primitives include memory primitives, data bus primitives, address bus primitives, read-port primitives and macro output primitives. In another embodiment, for modeling content addressable memories (CAMs), the ATPG memory primitives include memory primitives, compare port primitives and macro output primitives.

Abstract: A charge trapping semiconductor device is particularly suited as a replacement for conventional pull-up and load elements such as NDR diodes, passive resistors, and conventional FETs. The device includes a charge trapping layer formed at or extremely near to an interface between a substrate (which can be silicon or SOI) and a gate insulation layer. The charge trapping device can be shut off during static operations to further reduce power dissipation.

Abstract: Performing signal integrity (SI) analysis on integrated circuit designs is becoming increasingly important as these designs increase in size and complexity. Dividing a design into blocks can simplify the resulting analysis. Additionally, such blocks can be replaced with timing models, which provide a compact means of exchanging interface timing information for the blocks. To further increase the speed and accuracy of SI analysis, enhanced interface logic models (SI-ILMs) can be used. An SI-ILM can include cells in timing paths that serve as the interface between the block and other parts of the design. The SI-ILM can also include internal nets that have cross-coupling effects on interface nets and nets outside the block. By including these internal nets, SI analysis at the top-level can be both fast and accurate.

Abstract: Complex layout features, especially two-dimensional (2D) features such as jogs and corners, are more susceptible to photo-resist pinching and bridging, even with the use of optical proximity correction. These problems may arise due to unrealistic targets, e.g. square corners, thereby resulting in excessively aggressive correction in the vicinity of these 2D features. To provide a more realistic target, an aerial image can be sampled and its gradient computed at evaluation points on the 2D feature. The aerial image contains spatial information about the local pattern and the interaction of the pattern with the manufacturing process. This information can be used to predict a feasible shape or curvature for the 2D feature. The predicted shape can then be used to retarget the 2D feature based on realistic process capabilities.

Abstract: A method of modeling an edge profile for a layer of material is provided. The layer of material can include a resist and/or an etch. In this method, multiple models can be generated, wherein at least two models correspond to different elevations on the wafer. Each model includes an optical model, which has been calibrated using test measurements at the respective elevations. In this manner, an accurate edge profile can be quickly created using the multiple models. Based on the edge profile, layout, mask, and/or process conditions can be modified to improve wafer printing.

Abstract: A method and system that selects an operational mode for a peripheral that has an interface engine block. When the peripheral operates in the operational mode a clock signal to the interface engine block is disabled for at least a portion of time.