pitch of chip

hello all
I wanted to know…
In routing a VLSI chip, we can choose either a grid-less approach or grid approach. But when we choose a grid approach “on what all factors does the pitch of grid depends”?
is it type of technology
library cells.and what others factors decide grid pitch
thank you
Re: pitch of chip
the pitch of the grid depends on the technology
In old cmos technologies all pins were nicely aligned to the
routing grid that is on grid.
but wen we are designing sub micron less than 90 nm pins are no longer guaranteed to contain any ongrid location and may have to be accessed off grid, mainly in high density pins.
The pitch also have dependency on the routing path.