Resistance in metal wires

[phutanesv]

Dear dudes,

Resistance increses from (suppose there are four layers in design)

Metal 4,metal3, matal2,metal1

We also know that power stripes or rings should be nearer to core

means metal1 is nearer, which is higher resistance.

My doubt is do power stripes must be of higher resistant?

Phutane

 

[au_sun]

Phutane,
Metals used for Power stripe should have low resistant for the purpose IR drop.

Higher metals like M4 & M3 have low resistant compared to lower Metals M1 & M2.

so M4 & M3 are preferred for power stripes.

 

[phutanesv]

Dear au_sun,

So the core will at the bottom above this layer comes metal1,2, after that power stripes, but routing becomes lenghtier.

what about effects due to routing?

phutane

 

[s_prasan]

Power stripes are normally created in top metal layer. The stripes are designed to be wide to reduce resistance.

lower metal layers metal 2, 3, 4 are reserved for routing.

please specify what kind of routing effects u r reffering to?