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s today’s electronics systems continue
to shrink and become more complex
and pervasive, failures can cause costly
downtime, product delays and recalls, and de-
bilitating reputational damage. Finding and fix-
ing failures before they do damage is important,
but becomes increasingly challenging when
devices are built using ever more complex de-
signs. The solution is to employ a comprehen-
sive, multidisciplinary approach to electronic
system failure analysis. In addition, many fail-
ures can be avoided altogether by thorough
testing, coupled with the latest focused ion
beam (FIB) circuit edit techniques. These ad-
vanced methods quickly and inexpensively
debug and validate design fixes or explore de-
sign optimization opportunities in integrated
circuits (ICs) without having to commit to
costly and time-consuming full mask spins.
System complexity continues
Systems are becoming more complex at all
levels—board, die, IC, and package. Today’s de-
vices can contain billions of transistors, and in-
tegrate a wide variety of previously discrete
components and independent systems. With
the arrival of FinFET, metal gate, low-k dielec-
tric, and other advanced process nodes, devices
are getting even smaller. Packaging complexity
is also growing, with options including system-
in-package (SiP), multi-chip modules (MCM),
SiSub, stacked die, through-silicon via (TSV),
and Cu wire. Devices also increasingly feature
multi-layer metal stacks and are produced in
flip chip and other advanced chip scale form
factors. Meanwhile, the materials, coatings, and
molding compounds associated with advanced
packages and boards are also growing more
complex. In the power arena, many devices are
moving to silicon carbide (SiC), gallium nitride
(GaN), and other wide bandgap materials that
create additional challenges related to design
and characterization, process monitoring, and
reliability.
To make failure analysis even more difficult,
many failures occur only intermittently. System
challenges vary widely by industry and applica-
tion, with each functional element in a design
often requiring specialized domain knowledge
to understand a failure’s root causes and mech-
anisms. Networking and automotive systems
offer prime examples of the depth of today’s
failure analysis challenges. A networking sys-
tem can span multiple boards containing thou-
sands of components, including complex ICs
and SoCs that may also contain many types of
RF, power supply, high-speed digital, and stor-
age media.
Today’s automobiles are similarly complex,
containing as many as 100 electronic control
units (ECUs) or more, for systems ranging from
backup cameras to lane-changing warning sys-
tems. Further, tomorrow’s assisted driving and
sensor-guided autopilot systems are expected
to include a dozen ultrasonic detectors and
multiple cameras and radar sensors. Failures
can occur anywhere in a complex chain of
standalone and multiple interrelated systems.
Meanwhile, counterfeit components may also
have entered the automotive supply chain, in-
troducing additional risks and accentuating the
need for screening and analysis in addition to
various types of verification and authentication
tests against reliability specifications.
Failure analysis: The first line of defense
The ideal failure analysis approach must
span both electrical and physical analysis to op-
timize root cause identification and determine
the associated failure mechanism and how to
prevent future failures. The focus must be on
the entire system, including the electronics,
materials, and failure mechanisms occurring at
the IC transistor level (Fig. 1).
Effective failure analysis also requires highly
experienced and well trained technicians with
expertise that extends from the component to
the system level, along with a comprehensive
set of lab equipment. Failure analysis service
providers must be able to perform parallel pro-
ADVANCED MATERIALS & PROCESSES •
AUGUST 2014
23
Advanced Designs Pose Challenges for
Electronic System Failure Analysis
Finding and
fixing
electronics
failures is
more
challenging
than ever as
devices are
being built
with
increasingly
advanced
materials and
processes.
Taqi Mohiuddin
EAG Inc.
Sunnyvale, Calif.
Fig. 1 —
Multi-level failure analysis should extend across the full continuum of possible
root causes and failure mechanisms.
Pass/fail
Electrical
parameters
Isolated
electrical
data
IC/discrete
component
analysis
System (black box)
System characterization
Board level
Component level
Limited information,
corrective action not
possible
Helps localize failure and
determine next steps for
deeper investigation
Localize failure to PCB or
component level
Root cause analysis