FAQ

You will find  below a list of foundry FAQ. If the information you look for is not below, please contact foundry@ums-gaas.com

 

Why is the ADS PDK validity period limited?

To avoid the use of obsolete PDKs, UMS implemented one year validity period inside the PDKs. This prevents you from missing any PDK or model release when you decide to re-use your PDKs. One month before the date of validity end, you get a warning message when running ADS.  You can contact us to get a new PDK or a new license file to immediately unlock the PDK and remove the warning message.

What is the best snap grid unit for layout generation?

One micrometer is highly recommended. Generally speaking you don’t need to optimize a device dimension by less than 1µm.

Do I need to define by myself a stack for E/M simulations ?

No, our PDKs include all the parameters for automated 3D view generation from the 2D layout view.

I may find a strange component called PCON in the component pallet: what is its purpose?

PCON is a tricky element used for helping layout generation from schematic view of non grounded transistors. Symmetrical FET layout includes one electrical source node but two different layout ports. In case you want to connect different devices to the North and South parts of the FET,  please connect the PCON device on Source. The two other ports will allow you to connect two different elements.

What is the purpose of the “support areas” described in the Design Books?

When you use rubber tips for die picking it may be nice to have the tool in contact with these patterns, in order to avoid contact with air-bridges.

Why does UMS need an error free GDS before manufacturing?

Layout rules have been established to guarantee the feasibility of the process fabrication with a good level reproducibility and a good reliability behavior.

What is the purpose of the FDR organized by UMS before launching a fabrication?

The unique cumulated experience of UMS teams helps to create a list of points and questions to be checked before launching. It will secure  your design success  and your expected performance achievement with a high level of confidence.