N-MOSFET as high side switch

I was working with N-MOSFETs working as high side which needed gate driver ICs with bootstrapping circuit to achieve the appropriate gate to source voltage...So i was wondering about the processors with millions of MOSFETs inside them...they too ould be perfroming high side switching...how is this achieved in the processor since it is not very easy to integrate all those gate driving mechanisms to an IC.

a) For high-side switching you should use a P-channel MOSFET. b) MOSFETs can work perfectly at 5V/3.3V - look for "Logic Level MOSFETs" c) The MOSFETs inside ICs are very small and much easier to drive.

That is of course, precisely why we now use CMOS - Complementary pairs of N-channel on the low side and P-channel on the high side.

Prior to that, NMOS was used which was slower and consumed power even when not switching.