3 Automatic Needle Alignment
3-13
3.2.1 Tips on the pad registration
Selecting pads including
those in the both ends
Pad pitch change
Numbering of registered pads
1 2
3
1.5 mm
1.5 mm
1.
5 m
m
1.
5 m
m
With <PAD REGIST. END> button pushed at the end
of pad registration, all the registered pads are given
serial numbers as shown left, No. 1 for the one
nearest to the lower left corner of the die and
counterclockwise, independently of the order of
registering.
When some registered pads have been deleted with
<PAD DELETE>, pushing <PAD REGIST. END> has
the serial numbers rearranged for the remaining pads.
The serial numbers determine the order of the high
magnification pad alignment for the selected probe
tips.
For a die having pads positioned along all the edges
as shown left, when all the pads are registered, the
target pads are automatically chosen for the pad
alignment in the low magnification process as shown
left; one pad group near a die corner and another
group near the corner diagonal to the first corner in
order to ensure reliable and faster alignment for all the
probes and pads.
(For this type of pad arrangement, be sure to register
those pads in all the four corners; unless a corner pad
is registered, the corresponding probe tip position can
not be determined in the high mag. pad alignment and
its probe mark may have displaced over the pad
area.)
When a die has pads that are arrayed in one
horizontal or vertical line only as shown left, be sure to
register those pads existing in the ends of the pad
row. In the low magnification pad alignment process,
two pad groups including the end pads are chosen to
determine the position of the corresponding probe
tips.
For the low magnification pad alignment process, a
pad group where pads are arrayed in irregular pitches
(not in a constant pitch) is better for judging the
position of the corresponding probe tip images,
because the irregularity does not allow the probe tips
to position in various ways over the pad group.
