Currently I'm working on 40nm technology and the LEF has 7 metal layers named as M1 to M7. I have choosen M1 and M2 for POWER ring and stripes. Which metal is better for POWER ring and stripes ? Could you please explain me with an simple example?
please, check this solution, especially attached pdf. Usually, the higher layers for power routing are better, because they have lower resistance. Also, power stripes in M1, M2 will block std cell pins.
Thanks for your valuable reply.