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ELECTRONIC DEVICE FAILURE ANALYSIS | VOLUME 18 NO. 1
area so that it is greater than the submillimeter fieldof view.
For novel FIBs, there were two specific references. The
first was part of Jason Sanabia’s Raith nanoFIB presenta-
tion, where he discussed possible uses for liquid metal
ion source alloy-source-based beams. Raith now has alloy
sources available, and Jason showed various applications
that used gold, silicon, and AuGe cluster beams for nano-
pore and plasmonic device machining, respectively.
The second area of focus was the presentation by
Edward Principe (Tescan USA) on the use of xenon plasma
cusp ion sources for TEM prep and other applications.
Edward discussed the implementation of a rocking stage
into the dual-beam plasma FIB to help mitigate ion
beam channeling effects that cause curtaining during
cross sectioning and uneven milling due to varying grain
orientation. The basic idea is to normalize the material-
removal rate by varying the ion beam incident angle on
the substrate. Edward also reviewed the addition of new
detector hardware to enable large-area 3-D tomography
and time-of-flight SIMS in the Tescan dual-beamplatform.
The last area discussed in the Tescan presentationwas the
use of xenon beams for delayering. According to Edward,
the xenon beam is particularly good for this application,
due to its low current density in combinationwith Tescan’s
endpoint-detection system.
TEM sample preparation was a very strong theme in
this year’s User Group meeting, with three of the five pre-
sentations covering TEM prep and much of the following
discussion focusing on the subject. Jamil Clarke of Hitachi
High Technologies America discussed techniques and
tooling to achieve ultrathin, low-damage lamellae. The
two primary advancements are the inclusion of a seven-
axis stage and the incorporation of an argon or xenon ion
beam, to eliminate curtaining and to remove amorphasized
materials, respectively. The seven-axis stage allows the
user to reorient the sample during lamella preparation
to improve machining uniformity and eliminate curtain-
ing effects. The inclusion of an argon ion gun into the
dual-beam platform (making it a tribeam) enables in situ
removal of the damaged region of the lamella caused by
the higher-energy Ga+ ion beam.
Matt Bray of FEI Company presented a review of the
three-step process for creating TEM lamellae down to
7 nm. The three steps are “chunking,” the process of
undercutting the sample substrate; lift-out, the process of
moving the chunk from the sample to the TEM grid; and
thinning, removing all the material down to the region of
interest. Although these techniques are not new per se,
the presentation emphasized that all three steps are now
highly automated, which enables TEM prep access to a
less-experienced user base and improves overall efficiency
and prep quality.
The final area of TEMprepwas part of EdwardPrincipe’s
presentation on the Tescan xenon plasma dual-beamplat-
form. Edwarddiscussed the benefits of using a high-current
xenon beam to improve lamella prep throughput time. He
also discussed buildingmultiple windows into the lamella
to expand the analysis region of interest to larger areas.
At the conclusion of the five presentations, the attend-
ees’ discussion centered on the merits of using different
ion beam species and different beam energies for TEM
sample prep and other large-areamilling techniques. Much
discussion ensued on using xenon beams and damage
mitigation when using low-energy gallium or argon ions.
The audience was also interested in hearing about other
alternative ion sources, such as helium and neon gas-field
ion sources (GFIS) and cold beams. It was noted that there
was a talk on cesium cold beams in the 2014 User Group
and one on neon GFIS in the 2013 User Group but nothing
in 2015. Looking to next year, we will pick up the theme of
alternative beams and applications.
Quick and reliable sample preparation, from
electron-transparent transmissionelectronmicros-
copy (TEM) lamellae preparation to 3-D package
decapsulation, defines the success of any root-cause
ISTFA 2015 SAMPLE-PREP/3-D PACKAGE-PREP USER GROUP
Moderators: Jake Klein, Texas Instruments, and Rose M. Ring, Globalfoundries, Inc.
failure analysis (FA) project or request. Sample preparation
has been a key topic at ISTFA for decades. The Sample-
PreparationUser Groupmeeting has beenwidely attended,
and this year was no different. More than 60 attendees
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