DRC error(vertice is drawn off-grid)

[sw0ws1]

Hi
I have this DRC error (vertice is drawn off-grid)
what does this error mean?i have no information about it except the previous statement
can anyone help me???
thanks in advance

 

[dick_freebird]

Every PDK has a "grid" (lowest step you can place or move an
object to).

You have information. You have your foundry PDK docs and you
have your DRC deck. You could read the code and determine
what the grid is. Don't play helpless. Learn to dig.

These errors often come from a chop or merge gone bad,
creating a new vertex at a point you could not have drawn
by hand.

 

[Teddy]

When looking for the grid value try to find " manufacturing grid" it actualy says what resolution your masks will have. If you are off this grid on the mask and therefore on the silicon you might end up with for example narrower metal or smaller spacing then allowed.
Very often (if you use cadence) this error happens when drawing polygons with 45 degree edges or when you use path with 45 degrees and then convert it to polygon or flatten it. It is very anoying issue and to fix all the errors could be quite time consuming. But do not ignore those. It can mess up a lot of things

 

[s_ss]

In my design,I found that manufacturing grid was 0.01um, therefore all edges/corners of paths with dimensions in the range e.g 123.444 or 3.456 (3 digits after the decimal) were giving offgrid errors. A simple and easy way to deal with offgrid errors is to select the path or shape that is giving offgrid errors...then go to

Edit ---> Others---> Convert to Polygon

This will convert your path to polygon....(Converting your path to polygon doesnt alter your design.....And I think it that this method will work well if you convert any other shape to polygon)


Now if you select your polygon and look at its properties you will see all the co ordinates of corners of your polygon. You simply delete the third digit after the decmial e.g 123.444 will turn 123.44 (third digit removed).
This will not modify the shape of your path too much as it is the third digit dimension and will easily remove off grid errors.