Purpose of Metal Orientation

[B_hawk]

Hi Guys,

Can anyone please explain what is the purpose of following metal orientation in CMOS layout. It reduces routing congestion, any other purpose?

Thanks & Regards,

Karthik :razz:

 

[wics]

This is a terrible explanation probably, but if I understand your question clearly, then the concept of routing metal layers in only one orientation per layer comes from digital design. This concept I believe stems from the use of APR (Auto-Place & Route) tools, ease of layout, and prevention of layout issues.