Need advice for creating nS time delay

[sayzer]

...
...you can play with external logic gates ( if possible ...) and use their propagation time : time can easily fall to 10 nS ...

a single instruction @4Mhz is 1uSec, this will be impossible to be faster for this frequency.

I was thinking to charge a 10pF capacitor and wait for its discharge.
But before spending hours on its tests, should I keep thinking on this?
Don't we have a cap on our input pins already? that is another issue.