minEndOfLineEdgeExtension

Specifies an additional extension requirement when a cut shape lies near the end-of-a-line for the cut edge at the end of the line. The constraint does not apply to the end-of-line edge if it is greater than or equal to a given width. Width and cut class are required parameters for this constraint, and cut class must be a non-square cut class if the longEdgeOnly parameter is given.

• The extension may be a simple minimum extension, or optionally a smaller exactExtension may also be allowed.
• The constraint may not apply to edges with length less than eolWidth if those edges are not equal to the wire width (equalRectWidth).
• The constraint may also only apply to the extension of the end-of-line edge over the long/side edge of a non-square cut class (longEdgeOnly).

This constraint is not symmetric.

minEndOfLineEdgeExtension Quick Reference

Value Type

minEndOfLineEdgeExtension constraints have a Value that is the minimum extension of layer2 (metal) beyond layer1(cut).

Parameters

• width (Value, required) The constraint applies only to end-of-line edges with width less than this value, in user units.
• cutClass (DualValue, required) specifies the cut class for which this rule applies, given the cut class width and height.
• equalRectWidth (BoolValue, optional) specifies that the constraint only applies to end-of-line edges with length equal to the wire width.
• exactExtension (Value, optional) If specified, the overhang may match this value, instead of being greater than or equal to the constraint value. This parameter cannot be used with the longEdgeOnly parameter.
• longEdgeOnly (BoolValue, optional) If set and true, the constraint only applies to the long/side edges of a rectangular (non-square) cut at the end of the line. This parameter cannot be used with the exactExtension parameter.
• maxRectEnclosureArea (AreaValue, optional) If specified, the constraint only applies if the enclosure is rectangular and the area of enclosure is less than this value.
• concaveCornerLength (Value, optional) If specified, the constraint applies only if an edge adjoining an end-of-line edge that extends over the cut shape forms a concave corner with both concave edges less than this value in length.

Examples

Example 1—minEndOfLineEdgeExtension with longEdgeOnly

In this example, for end-of-line width <= 0.15, there must be a minimum 0.04 extension of Metal1 past V1 at the long/side edge of a VB cut (0.06 wide and 1.0 in height) at the end of the line.

set_constraint_parameter -name width -Value 0.15
set_constraint_parameter -name cutClass -DualValue {0.06 0.1}
set_constraint_parameter -name longEdgeOnly -BoolValue true
set_layerpair_constraint -constraint minEndOfLineEdgeExtension \
 -layer1 V1 -layer2 Metal1 -Value 0.04 

PROPERTY LEF58_EOLENCLOSURE
  "EOLENCLOSURE 0.15
    CUTCLASS VB
    LONGEDGEONLY 0.04 ; ";

orderedSpacings(
  (minEndOfLineEdgeExtension V1 Metal1
    'cutClass (0.6 0.1)
    'width 0.15
    'longEdgeOnly
    0.04 )
) ;orderedSpacings

Example 2—minEndOfLineEdgeExtension with equalRectWidth and exactExtension

In this example, for end-of-line width <= 0.15, there must be a zero or minimum 0.05 extension of Metal1 past V1 for square VA cuts (0.06 in width and height) at the end of the line. The constraint applies when the end-of-line edge has a length equal to the wire width.

set_constraint_parameter -name width -Value 0.15
set_constraint_parameter -name cutClass -DualValue {0.06 0.06}
set_constraint_parameter -name exactExtension -Value 0.0
set_constraint_parameter -name equalRectWidth true
set_layerpair_constraint -constraint minEndOfLineEdgeExtension \
 -layer1 V1 -layer2 Metal1 -Value 0.05 

PROPERTY LEF58_EOLENCLOSURE
   "EOLENCLOSURE 0.15 EQUALRECTWIDTH 
       CUTCLASS VA 0.05 0.0 ; " ;

orderedSpacings(
  (minEndOfLineEdgeExtension V1 Metal1
    'cutClass (0.06 0.06)
    'width 0.15
    'equalRectWidth
    'exactExtension 0.0
    0.05 )
) ;orderedSpacings

Example 3—minEndOfLineEdgeExtension with maxRectEnclosureArea

In this example, the value of minEndOfLineEdgeExtension is 0.025 under the following conditions:

• The width is less than 0.2µm.
• The enclosure must be rectangular and the area of enclosure is less than 0.05µm.
  

  Format	Example
  Tcl	set_constraint_parameter -name width -Value 0.2 set_constraint_parameter -name maxRectEnclosureArea -IntValue 0.05 set_layerpair_constraint -constraint minEndOfLineEdgeExtension \ -layer1 V1 -layer2 Metal1 -Value 0.025

  Illustration for minEndOfLineEdgeExtension with maxRectEnclosureArea
  

Related Topics

Extension Constraints