A method for identifying an area of a chip to be probed proceeds as
follows. A callout list of failures is obtained from a tester, the list
including cell name and pin for each failure. A Def file is interrogated
to locate a Def entry matching the cell name, and a cell type, cell
location, and cell orientation data is obtained for the cell from the Def
file. A Lef file is then interrogated to locate a Lef entry matching the
cell type, and the coordinates of the pin are obtaining from the Lef
file. A GDS file is interrogated to locate a GDS entry matching the cell
type, and the coordinates of polygons listed in the GDS entry are
obtained. The coordinates of the pin are then crossed with the
coordinates of the polygons to identify overlapping area. The overlapping
area is defined as the location to be probed. A driving signal is applied
to a stage to align a prober with the location to be probed.