51 results about "Layout Versus Schematic" patented technology

The present invention relates to a method for efficiently performing hierarchical design rules checks (DRC) and layout versus schematic comparison (LVS) on layout areas of an integrated circuit where cells overlap or where a cell and local geometry overlap. With the present invention, a hierarchical tree describes the integrated circuit's layout data including cells having parent-child relationships and including local geometry. The present invention performs efficient layout verification by performing LVS and DRC checking on the new portions of an integrated circuit design and layout areas containing overlapping cells. When instances of cells overlap, the present invention determines the overlap area using predefined data structures that divide each cell into an array of spatial bins. Each bin of a parent is examined to determine if two or more cell instances reside therein or if a cell instance and local geometry reside therein. Once overlap is detected, the areas of the layout data corresponding to the overlap areas are selectively flattened prior to proceeding to DRC and LVS processing. During selective flattening of the overlap areas, the hierarchical tree is traversed from the top cell down through intermediate nodes to the leaf nodes. Each time geometry data is located during the traversal, it is pushes directly to the top cell without being stored in intermediate locations. This provides an effective mechanism for selective flattening.

An integrated verification and manufacturability tool provides more efficient verification of integrated device designs than verification using several different verification tools. The integrated verification and manufacturability includes a hierarchical database to store shared design data accessed by multiple verification tool components (e.g., layout versus schematic, design rule check, optical process correction, phase shift mask assignment and machine language conversion). The hierarchical database includes representations of one or more additional, or intermediate layer structures that are created and used by the verification tool components for operations performed on the design being verified. Use of a single hierarchical database having shared data for access and use by multiple verification components streamlines the verification process, which provides an improved verification tool.

A sub-circuit based extraction method which extracts a multi-finger MOS transistor directly as a sub-circuit is described. By adding three marking layers, the method provides the layout extracted netlist with a complete list of device geometric parameters corresponding to the device properties as presented in the sub-circuit model based schematic netlist. By performing a layout-versus-schematic comparison based on all geometric parameters extracted, the layout checking is performed in a complete and accurate way where each device parameter is checked against the corresponding design schematic. This complete and accurate geometric parameter comparison enhances the confidence level of the layout physical verification.

An integrated verification and manufacturability tool provides more efficient verification of integrated device designs than verification using several different verification components. The integrated verification and manufacturability includes a hierarchical database to store shared design data accessed by multiple verification components (e.g., layout versus schematic, design rule check, optical process correction, phase shift mask assignment and OPC verification and machine language conversion). The hierarchical database includes representations of one or more additional, or intermediate layer structures that are created and used by the verification components for operations performed on the design being verified. Use of a single hierarchical database having shared data for access and use by multiple verification components streamlines the verification process, which provides an improved verification tool.

This paper describes an EDA (Electronic Data Automation) method and computer software invention for connectivity verification of IC mask Layout database versus IC Schematic; LVS Check (LVS: IC Layout versus IC Schematic) over the internet. The technique takes advantage of a unique algorithm to check the mask layout database connectivity, compare it with its corresponding schematic diagram for any mismatches in the mask layout polygons connections. The input of the tool is a mask layout database blocks (i.e.: IC layout) that were made manually and/or automatically using synthesized tools. These blocks may have some connectivity mismatches that need to be fixed in order to match the corresponding integrated circuit (IC) schematic diagrams. The output of the software tool is a text based descriptive log file and errors markers pointers that may be read into the mask layout database in order to point any connectivity mismatches of the mask layout database, comparing it to its corresponding schematic diagram. The end result is a mask layout set of markers and a text format log file that describes any mismatched connections in the mask layout database, comparing it to its corresponded schematic diagram. The software performs on individual mask layout blocks and/or on hierarchical structure of mask layout blocks. The system works hierarchically and/or flat. System also checks mask layout database incrementally, means only blocks that have been changed are checked. The system can be run via the internet using our secured protocol. The system offer a web based control panel to execute all necessary setups for submitting LVS check over the internet. The system offers the option to run on a local machine (user's computer) or on the main server over the internet. (Inventor's computer) The system also offers a PDA (Personal Digital Assistant) interface to launch LVS runs via industry's standard PDA's. The procedure is fully secured by 128 bit security protocol. All necessary file including mask layout GDSII (or GDSIII) file, netlist and technology file are securely encrypted using 128 bit protocol and send to the remote server. These files are decrypted and submitted for LVS check on the remote servers. The main remote server is distributing the task among other computer system for advanced parallel processing to achieve fast results. All results log files are encrypted using 128 bit security protocol and available for download by the user. In case of local LVS check the results files are available on the user's local machine.

A method and system for validating integrated circuit designs that are built with encrypted silicon IP blocks decrypts the encrypted silicon IP blocks in the integrated circuit designs with the keys from IP providers. After decryption, various validation checks on the integrated circuit designs are done, such as design rule check (DRC), layout versus schematic (LVS) check, parasitic resistor capacitor (RC) extraction, circuit simulation, signal electro migration (EM) and voltage drop check, signal integrity (SI) check and static timing check, etc. After validation, any confidential data from the checking results related to the encrypted silicon IP blocks are themselves encrypted to protect the proprietary silicon IP blocks. The method and system work with silicon IP encryption technology to establish a low cost silicon IP usage and verification platform, and to enable a more cost efficient silicon IP business model.

A layout versus schematic (LVS) comparison tool determines one-to-one equivalency between an integrated circuit schematic and an integrated circuit layout by performing operations to color a schematic graph of a parent cell to an equilibrium state. An operation is then performed to recolor nets connected to first and second child cells having the same device value within the parent cell, using a net coloring operation that recolors a first plurality of symmetric pins of the first child cell and recolors a second plurality of symmetric pins of the second child cell. Distinct device values are then generated for the first and second child cells by determining a first product of the colors of the recolored first plurality of symmetric pins and a second product of the colors of the recolored second plurality of symmetric pins. The operations to recolor the nets preferably include coloring a first pin of a child cell within a parent cell using a pin coloring operation that is a function of a device value of the child cell and a color of each of the pins of the child cell that are independently swappable with the first pin, but is independent of a color of a second pin of the child cell that is dependently swappable with the first pin.

The invention discloses a method for standard cells using an FinFET standard cell structure with polysilicon on OD edges. FinFET transistors are used to define the standard cells, and the standard cells comprise grid structures forming a transistor at a crossing point with a semiconductor fin. Polysilicon pseudo-structures are formed in active areas of the standard cells or edges of OD areas. In a design process, a pre-layout netlist schematic diagram for the standard cells includes a three-terminal MOS device corresponding to the polysilicon pseudo-structure at the edges of the standard cells. After automatic placement and routing processing, standard cells are employed to form a device layout, and a post-layout netlist is extracted. If two standard cells are contiguous, a single polysilicon pseudo-structure at the common boundary is formed. A layout-versus-schematic comparison is then performed in which the pre-layout netlist and the post-layout netlist are compared in order to verify the obtained layout. The invention also discloses a layout verification method used for a polysilicon cell edge structure in FinFET standard cells.

A collaborative environment for performing physical verification processes on integrated circuit designs. Multiple physical verification results may be stored in a “unified” results database/directory (e.g., unified at least from a user's perspective), where results from various verification processes, such as Design-Rule-Check (DRC) processes, Layout-Versus-Schematic comparison (LVS) processes, Design-For-Manufacturing (DFM) processes Optical Proximity Correction (OPC) processes, and Optical Rule Check (ORC) processes are accessible from the same style of user interface, which may be a graphical user interface. The basic abilities for design team-based interactions can be equally available to each process involved in the physical verification of an integrated circuit design.

Techniques and mechanisms for the use of layout-versus-schematic (LVS) design tools to validate photonic integrated circuit designs. Various implementations employ alternate analysis techniques with LVS analysis tools to perform one or more LVS analysis processes on photonic integrated circuits. These analysis processes may include curvilinear design validation and the associated flow implementations.

The invention discloses a method for comparing a hierarchical net list of an integrated circuit, which belongs to the field of semiconductor integrated circuit design automation, and is mainly used for layout versus schematic consistency check during a rear-end layout design. Hierarchical units are compared by transmitting matching information of a port and a pin, and the iteration cycle of the rear-end layout design is shortened. The method is implemented by the following steps of: performing hierarchical preprocessing on the hierarchical net list, comparing the hierarchical units in turn according to a reverse topological sequence, and adding hierarchical units which cannot be completely matched in the comparison process to the tail part of a suspended queue; and processing the hierarchical units in the suspended queue by using a topological sequence induction method and a reverse topological sequence broadcasting method circularly, processing by a hierarchical random matching method when the induction method is ineffective to all suspended units, and repeating until the suspended queue is empty.

The invention discloses an automatic positioning method for physical short circuit positions among multiple line networks, and belongs to the technical field of electronic design automation. The method comprises the following steps of: receiving a circuit diagram/circuit network table, physical layout data and layout versus schematic (LVS) result data; and establishing an abstract diagram according to the circuit diagram/circuit network table, the physical layout data and the LVS result data, and simplifying the abstract diagram so as to complete automatic positioning of physical connection short circuits of the multiple line networks on the simplified abstract diagram. By using the method, automatic positioning of the physical short circuits among the multiple line networks during integrated circuit physical layout design can be automatically realized to replace a designer to manually seek the physical short circuit positions on the physical layout, so that the design efficiency of the physical layout is improved.

There is provided a method for verifying inter-stratum connectivity for two or more strata to be combined into a 3D chip stack. Each of the two or more strata has 3D elements including active 3D elements, mechanical 3D elements, and dummy 3D elements. The method includes performing a respective 2D layout versus schematic verification on each of the two or more strata with respect to at least the 3D elements to pre-ensure an absence of shorts between the 3D elements when the two or more strata are subsequently stacked into the 3D chip stack. The method further includes checking inter-stratum interconnectivity between each adjacent pair of strata in the 3D chip stack.

The invention discloses a method for identifying a short-circuit path in an integrated circuit layout verification process, belongs to the technical field of integrated circuit computer aided design, and particularly relates to the field of integrated circuit layout design rule checking (DRC) and layout versus schematic (LVS). The invention aims at providing a method for quickly searching the short-circuit path in a layout database. The problem of searching the short-circuit path in the layout database is transformed into the problem of the shortest path between appointed top points in an undirected graph through abstract expression, and the solution space is divided into a plurality of subspaces independent of each other according to the connectivity characteristic of the undirected graph, so that the algorithm complexity of problem solving is lowered; and meanwhile, the multi-point breadth-first shortest path search algorithm is adopted according to the characteristics of large data volume and complex connection relation in integrated circuit design, so that the required storage space is smaller and the running efficiency is higher relative to the general search algorithm.