Minimum Required Version
: Expert 4.14.0.R, Guardian 4.14.0.R

This example will demonstrate how the Guardian DRC tool can be used to find layout objects that are intersecting.

1. Preliminary steps

To run this example, open a Guardian DRC session and choose
File->Open
to load the project
“drc_ex11.eld”
. Then open the top cell
drc_ex11
using the
Cell->Open…
menu.

2. Intersection command for error detection

This command checks for intersections of region boundaries in the input layer. This is a single input layer syntax.

The syntax for this rule is:

   Intersection: Layer=  < input layer identifier >,
                 LayerR= < result layer identifier >,
                 Options = (list of check options),
                 ID = < error identifier >;

in which:

• Layer
  is the layer name being measured
• LayerR
  is the layer name in which the geometries of the layer with intersection would be saved
• Options
  is the list of additional option to the check
• ID
  is the error message that would be display and listed in the log when the error occur

This check can detect any intersection of the input layers or ONLY the self-intersection of a given layer geometries.

Figure 1
, illustrates the syntax that can be used to implement this command. Two different syntaxes were implemented to illustrate the different options available.

For the “Intersection” operation, the only options allowed are: S, S+, I, IS, L and L1.

A detailed description of all options can be found in the
Guardian DRC user manual
section
2.3.9.1: Common Syntax: Parameters and Options.
Section 2.3.9.8 describes the Intersection command. The user manual
“guardian_users1.pdf”
can be found in
lib/expert/4.14.0.R/docs/
in your installation area.

3. Experimenting with the Intersection command

Once all of the example files have been downloaded and the preliminary steps describes in 1.0 are completed,
complete the following steps:

• Choose
  Verification->DRC->DRC Script panel
  . In this new window, choose
  File->Open…
  and select
  “intersection_01.dsf”.
  
• Press
  DRC->Run
  
• To inspect the errors, choose
  Verification->DRC->Errors->Load errors…
  you should get a window as shown in
  Figure 2.
• Select the last check and press the
  Load
  button located at the bottom of the window. Then choose
  Verification->DRC->Errors->First error
  to display the error in the layout, as shown in
  Figure 3
  .
• To unload the error choose
  Verification->DRC->Errors->Unload errors
  .
• You can repeat the load error process to inspect the other intersection errors being reported.

Note that these two
toolbars
can be used to access the DRC menu command. To turn the visibility of the toolbar ON and OFF, choose
View->Toolbars
and select
DRC
and
DRC error inspection.

Guardian DRC can also be launched from within the layout editor tool Expert. Within an Expert
session follow the steps described in 1.0 to open the eld file. Then choose
Verification->DRC->DRC Script panel.
In this new window, choose
File->Open…
and select desired DRC script. The rest of the steps are identical to the Guardian DRC flow.

Output Results

Input Files

intersection_01.dsf

//****************************************************************//
//         Example DRC rule for INTERSECTION check operation       //
//****************************************************************//

// Layers mapping definition section
Layers:
  act		( 43, 0	/* mapped */)
, po1           ( 46, 0	/* mapped */)
, m1           ( 49, 0	/* mapped */)
;

// commented out otherwise no intersection will be flagged
//Merge_input: on;  

// find any intersection of Metal1 layer geometries
Intersection: Layer=m1, options=(IS),ID="Intersection of Metal1";

// find self-intersection only of Metal1 layer geometries
Intersection: Layer=m1, LayerR=SI_met1, options=(I,IS),ID="SELF-Intersection of Metal1";


// END of DRC check