A method and apparatus for creating a phase shifting mask and a structure mask for shrinking integrated circuit designs. One embodiment of the invention includes using a two mask process. The first mask is a phase shift mask and the second mask is a single phase structure mask. 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. Both masks are derived from a set of masks used in a larger minimum dimension process technology.

Phase shifting circuit manufacture method and apparatus

Techniques are provided for extending the use of phase shift techniques to implementation of masks used for complex layouts in the layers of integrated circuits, beyond selected critical dimension features. The method includes identifying features for which phase shifting can be applied, automatically mapping the phase shifting regions for implementation of such features, resolving phase conflicts which might occur according to a given design rule, and application of assist features and proximity correction features. The method includes applying an adjustment to a phase shift mask pattern including a first and a second phase shift window, and a control chrome with a control width, and/or to a trim mask pattern having a trim shape with a trim width based upon one or both of a rule based correction and a model based correction to improve a match between a resulting exposure pattern and a target feature.

Phase shift masking for complex patterns with proximity adjustments

Layout processing can be applied to an integrated circuit (IC) layout using a shape-based system. A shape can be defined by a set of associated edges in a specified configuration. A catalog of shapes is defined and layout processing actions are associated with the various shapes. Each layout processing action applies a specified layout modification to its associated shape. A shape-based rule system advantageously enables efficient formulation and precise application of layout modifications. Shapes/actions can be provided as defaults, can be retrieved from a remote source, or can be defined by the user. The layout processing actions can be compiled in a bias table. The bias table can include both rule-based and model-based actions, and can also include single-edge shapes for completeness. The scanning of the IC layout can be performed in order of increasing or decreasing complexity, or can be specified by the user. The appropriate layout processing actions are applied to matching portions of the IC layout to form the corrected photomask layout. This process can be sequential or batch mode. Shape and action conflicts can be resolved by marking identified/modified elements or by designing rules for orderly resolution of any inconsistencies or overlaps.

General purpose shape-based layout processing scheme for IC layout modifications

Phase information is incorporated into a cell-based design methodology Standard cells have four edges: top, bottom, left, and right The top and bottom edges have fixed phase shifters placed, eg 0 A given cell C will have a phase set created with two versions: 0-180 (left-right) as well as 180-0 Alternatively, the same phase set: 0—0 and 180—180 could be created for a cell The phase sets are selected based on the ability to phase shift the features within the cell C By creating a phase set for most of the cells of a cell library, standard cell placement and routing techniques can be used and phase can then be quickly assigned using a simple ripple technique This ensures a phase compliant design upfront for the standard cell areas In some instances, phase sets are created for every cell in a library

Standard cell design incorporating phase information

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.

Design data format and hierarchy management for processing

PURPOSE: To provide a motor driven sliding type variable resistor having a driven pulley easily supported with a frame. CONSTITUTION: A first and a second support plate 17 and 16 are disposed face to face on a frame, elongated holes 17a and coupling hole 16a are formed face to face through the plates 17 and 16, and a groove 20a is formed into the top face of a support shaft 20 inserted into an axial hole of a drive pulley 10. This groove 20a allows the upper and lower ends of the shaft 20 to slide into the interiors of the holes 17a and 16a, utilizing the tension of the belt 11 when inserted into the hole 17a so as to hold the plate 17.

Masahiro Asano

Papers

Motor driven sliding type variable resistor