How to calculate resistance with respect to long connection lines? (Cadence)

[MK28]

hi all, i am doing layout in Cadence now....just a question...is it so that top thick layer (e.g M6 layer) provide low resistivity to propogating signals.....? Can anyone explain , hows that?

One more, i have some long connections in my layout.....how can i calculate the resistance with respect to this length of these lines....any formula ?

please.....

 

[safwatonline]

layout

1- yes , as u said it is thick >> R= raw *l/A=raw*(l/W)/d
>>>> resistivity is constant for a metal "Cu or Al" but here we mean by resistivity =raw /d ; d is the thickness
so resistivity inversly prop. w.r.t. d

 

[dgy99]

Re: layout

R = (sheet resistance) * (number of squares)

but at a corner, resistance is a little different.

I guess ur design rule document, from foundry, mention about sheet resistance of each metal layer.

good luck..