Why need thick route for clock trunk?

[cafukarfoo]

Hello,

Can anyone share why we need thicker route for clock trunk?

Thanks.

 

[llbaobao]

often we use higher metal as clock routing, for example in a 6al proc,we use 6al and 5al as clock routing, of course we can use 5al and 4al as clock routing.
the parasitic res of thicker metal is small.

 

[nikhilindia85]

Clock nets r highly switching nets and needs less delay to reduce the skew,slew etc...
high metal layers have less resistance and in order to reduce the crosstalk we use shielding or isolation