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ELECTRONIC DEVICE FAILURE ANALYSIS | VOLUME 19 NO. 1 confirmed the flatness of the surface and its suitability
for nanoprobing because of slightly raised metal/via and
transistor contacts over the insulator/dielectric layers.
Mr. Christian Catalan of Rasterly Lab was the last
speaker. He discussed the importance of and the chal-
lenges facing failure analysis and probing engineers in
data management and analysis for nanoprobing. He
shared his thoughts onwhat makes an effectiveworkflow
as well as useful data summary charts. He demonstrated
an advanced data analysis platform that addressesmany
of theaforementioned issues. It is aweb-basedapplication
that caters to collaborative teams, reduces the depen-
dency on scripting solutions such as Excel, and introduces
advanced capabilities such as saved sessions, searchable
analyses, and effortless collaboration with colleagues.
In the broader scope, this is a call for standards in data
analysis, so that workflow can be universal and highly
accessible to nanoprobing users.
ISTFA 2016 CONTACTLESS FAULT ISOLATION
USER GROUP
Moderators: Patrick Pardy and Dan Bockelman, Intel Corporation
Over the past few years, the Contactless Fault
Isolation User Group has looked for innovations
and research on how to move the capabilities
forward for future process geometrical scaling. Some
presentations were given in topic areas such as higher-
numerical-aperture lenses, shorter wavelength usage,
and so on. Although these developments will be very
important moving forward, we continue to use a very
large industry-installed base of current technologies to
perform failure analysis and debug of our products. This
large number of tools represents a huge capital outlay
for many companies, so the use of them for an extended
period of time continues to be imperative. Therefore, this
year’s focus for the Contactless Fault IsolationUser Group
centeredonboth innovation and efficiency for the existing
industry standard infrared-based optical probe toolset.
We want to “wring” every cent of value that we can from
these tools until the next inflection point is reached due
to fab process and where the future of the industry leads.
Dr. Krishna Kuchibhotla of Checkpoint Technologies
gave the presentation “Unique Dual-Beam Interferometer
for Probing ICs.” This new IC-probing technology show-
cases a dual adjustable laser beam using phase-shift
interferometry. The new hardware splits the incident
beam into probe and reference beams, which can be
moved independently of each other. A phase shift inter-
ferometer splits the beam into two separate beams, with
a phase difference that can be adjusted between 0 and
2 p. Precision phase control allows the operator to obtain
a good fringe contrast, which provides improved signal
detection. The operator can use the probe beam for
probing and park the reference beam anywhere within
the permissible piezo field of view. The hardware also
provides shutter capabilities to shut off one of the beams.
The tool name is SOM-DBI, for laser scanning optical
microscopewith integrated dual-beam interferometer. An
upgrade option for the DBI is available for existing tools.
The new capability uses the same software but adds a
newgraphical user interfacewindowwith a second beam
(green color) that can be moved around independently
from the existing beam (red color). Either unseparated
or separated dual-beam modes can be used, but the
separated mode offers an improved signal. An example
was shown that illustrated howusing unseparated versus
single mode gave a +3 db signal improvement. Another
example showed that for a small node, the aligned dual-
beamconfiguration provided +1.7 db improvement when
compared to using a single-beam configuration only. In
summary, this is a unique method of DBI with adjustable
x, y , and z flexibility for the two beams.
Mr.Neel Leslieof FEI/ThermoFisher ScientificCompany
gave the second presentation, “Advanced CW Laser
Voltage Probe Technique: Imaging Non-Periodic Signals.”
Anew technique, known as laser voltage tracing (LVT), was
presented. This technique adds a gated integrator to get
past any limitations of the spectrum analyzer. The test
loop frequency and number of averages determine the
hardware bandwidth. Subtraction is done between the
gate and gated signal, and the result is digitized by the
laser scanning microscope. When anomalies occur, the