Transcript Electrosort Automation Die Sorting vs. Wafer Probe

Electrosort Automation
Die Sorting vs. Wafer Probe
Die Sorting
Wafer Probe
 Screens out electrical failures before
assembly, thus improving assembly &
final test yield, which reduces overall
manufacturing cost.
 Screens out electrical failures before
assembly, thus improving assembly &
final test yield, which reduces overall
manufacturing cost.
 Screens out die that were damaged
during dicing & demounting process
before packaging, thus reducing
overall manufacturing cost.
 Does not screen out die that were
damaged during dicing & demounting
process, resulting in lower assembly
yields and higher costs.
Electrosort Automation
Die Sorting vs. Wafer Probe
Die Sorting
Wafer Probe
 Sorts die into bins, allowing only those
die needed for current orders to be
packaged, without scrapping other
bins that may be usable for future
orders. This improves die utilization,
yield, and cost. Ideal for Zener & TVS.
 Only pass/fail testing & inking. Either
all passing die must be assembled
resulting in un-needed packaged
devices or the wafers are probed to
tighter spec resulting in poor die yield.
Either way, costs are higher.
 Adds flexibility by making it possible to
assemble different bins into different
package types, if desired. This
improves die utilization, improves final
yield and reduces overall cost.
 Since wafer probing is unable to sort
different die for different packages,
unwanted die get assembled in the
wrong package or the wafers are
probed to tighter spec resulting in
poor die yield. Either way, costs are
higher.
Electrosort Automation
Die Sorting vs. Wafer Probe
Die Sorting
Wafer Probe
 Since EA equipment has Kelvin probes
on both the bottom & top of the die, it
is possible to measure voltage at
higher currents with more accuracy.
 Since wafer probing only allows Kelvin
probes on the top of the wafer, it is
unable to measure voltage accurately
at higher currents.
 Soft-touchTM probing minimizes
scratches to die.
 Probes often scratch die. This is
especially bad for Schottky diodes.
 Die sorting can be a continuous
operation, with no need to stop
between wafers.
 Testing must be halted to place the
wafer on the chuck & for alignment.
Probing must also be stopped to
replace ink from time to time.
Electrosort Automation
Die Sorting vs. Wafer Probe
Die Sorting
Wafer Probe
 With die sorting there is no messy ink
to deal with and no time wasted
curing the wet ink.
 With wafer probing/inking, user must
deal with messy ink and waste time
curing inked wafers.
 If die were tested with wrong
program, they can easily be retested.
 If die were tested with wrong
program, the ink must be washed off.
If error was discovered after ink is
cured, it is very difficult to remove the
ink.