cg
Refering to static leakage portion (subshreshold-leakage), for a 3GHz+ design you would have to choose a transistor geometry different from what you would choose for a 2GHz+ design, resulting in different static leakage-characteristics. However, this portion of leakage is not the challenge nowadays (although not neglectible, as it still contributes significantly). Dynamic leakage is predominant already, more precisely the gate leakage portion of it. K.