What is Polygon and what is path in IC layout?

[sathi.ec]

In an IC Layout, what is Polygon and what is path?
What are the advantages and disadvantages of each?

Thanks
Sathi

 

[zhancangF117]

IC Layout

Polygon is used to draw complex shape of metal or poly.
Path usually to draw bus or interconnection straight.

 

[vijay.kumarreddy]

Re: IC Layout

Paths are used to connect the general purpose interconnects , 90 degree bends...

Where as the polygons also serves the same purpose as that of the paths but these are more useful in drawing the 45 degree bends at the chip corners.
45 deg pathe are not acceptable ,u will get the offgrid errors.....by the tools like VLE,VXL..(Cadence)

vijay

 

[layout_designer]

Re: IC Layout

One main advantage of polygon over path is it aligns perfectly with grid for any angle.

Regards

 

[pratyusha]

Re: IC Layout

for path the width is set by default to the min width of that layer . it is very easy to draw for 90 degree . but for other angles polygons are used. with paths other than 90 degrees we get 'offgrid " errors

 

[vbhupendra]

Re: IC Layout

path gives no layout off grid errors.

 

[pratyusha]

Re: IC Layout

we got offgrid errors while doing tapeouts and rectified them with polygons.

 

[vijay.kumarreddy]

Re: IC Layout

Paths with 45 deg bends will definitely give the offgrid errors..
where asthe polygons with 45 deg wont give any offgrid errors...

vijay