🚀 go-pugleaf

>   Some points about landing probe pads inside a design chip seems to
be unclear to me.
> Hope some kind soul would be able to help me out.
> 
>   Say I want to probe a point in the circuit, which is a point inside
a standard cell.
> Since standard cells are designed very compact - I have the following
question. Is the
> standard practice is of landing probe pads inside standard cell, or
that of taking a
> metal(?) wire out from the point and placing the probe point at a
convenient point
> outside standard cells. 
> 


typically a picoprobe can be safely manipulated for
distances in ten's of microns (a 20x20 u pad would be
enough).

However, most common practice today is to use voltage-contrast
enhancement techniques on ebeam reflections. A 5x5 pad in topmost 
metal layer would be sufficient. If surrounded by a ground line, it
would be even better. Of course, the tester would cost more.


Rajesh
725-1776 CSL Modulars I				rgupta@sirius.stanford.edu