Hello,
I am working with 0.18um Technology, I designed my layout in mentor graphics IC station using tsmc018 process and rule. When I open GDSII file in klayout which is extracted from Mentor, Gate length is 2um which is wrong it should be 0.18um. So Is there any setting in Klayout for technology set?
Regards,
Rakesh
Comments
Hi Rakesh,
you don't need any technology setup in KLayout to get the dimensions right. GDS is specifying dimensions inside the format through "database unit" and "user units". Maybe there is something wrong with that in your case. The important number is "database unit in meters" which you can inspect in File/Layout Statistics. It should match your export settings.
Another reasons may be intentional scaling. Are you working with MOSIS SCMOS rules for example?
Matthias
Yes I am working with MOSIS SCMOS rules in mentor IC station.
Rakesh
So How can I solve this problem.?
Regards,
Rakesh
Hi Rakesh,
if you use SCMOS rules, the scaling is intended. That is implied by "scalable" CMOS. The idea is that you draw your layout on a technology independent scale and scale it down according to your target technology. I assume that 2 micron is the technology-independent width and your foundry will scale it down to 0.18 micron by applying a scale factor of 0.09.
I don't know how IC station gives you 0.18. I guess they use some specific user dimensions. I tried to avoid the confusion related to that, so KLayout always uses micron units and does not have the concept of user units.
You can use "display transformations" to simulate the scaling. Here is some receipe (for which I assume a scaling factor of 0.09):
The effect will be a scaling of the views. I am not quite sure if that aligns well with drawing grids and similar, but it's worth a try. Once you have established such a scaled view, you can save the layer properties into a .lyp file and attach it to a technology.
Matthias
I think the scaling can be done by opening GDS, followed by "Save As" with scaling factor of 0.09 in GDS save options, right?