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package interactions. Artifact-induced without exposure to atmosphere, site-specific cross sections of deeply
cracks from traditional cross sections preventing oxidation of defects prior to buried structures (Figure 2). The
look exactly like the type of real defects their analysis, and the entire workflow integrated system is versatile as it can
observed from reliability failures. For this (Figure 1) can be completed rapidly be applied to all the traditional Ga+ FIB
reason, while it is always challenging to because it exists within a single applications that require high resolution
make an artifact-free cross section, it is instrument with no requirement to and accuracy for semiconductor analysis,
even more so with advanced packages. manage different instrument queues or such as TEM sample preparation.
repeat the sample set-up, as would be
CSR: What kinds of innovations or required with a non-integrated solution. Biography
discoveries led to the combination of Some people think a plasma focused Raj Jammy is President of the Process
hardware in a single instrument that is ion beam PFIB integration with a laser Control Solutions business unit at Carl
vital to the Crossbeam laser system? would be a better choice for processing Zeiss Semiconductor Manufacturing
RJ: We have implemented a patented large volumes. However, the purpose Technologies group and President of
architecture that maintains the laser of the FIB in the workflow is for fine Carl Zeiss SMT Inc., the North America
ablation in a chamber that is integrated polishing, and the reality is that a Ga+ subsidiary of Carl Zeiss SMT GmbH.
into the FIB-SEM, yet segregated beam has significantly higher current With 25 years in the semiconductor
from the FIB-SEM chamber. The large densities than a PFIB at the typical low industry, Dr. Jammy has previously
volumes of ablated material tend to currents used for fine polishing. The fs- held executive leadership positions at
coat surfaces. The ZEISS architecture laser speed of large-volume material IBM, SEMATECH and Intermolecular.
maintains the pristine condition of removal, combined with the Ga+ beam He received a doctorate in Electrical
the imaging chamber for high-quality resolution and high current density for Engineering from Northwestern U. Email
imaging at highest SEM resolutions. fast fine polishing with highest process raj.jammy@zeiss.com
The sample can be shuttled between accuracy, results in an effective solution
the ablation and imaging chambers that provides the fastest workflow for

Rapid analysis of buried 2.5/3D package structures

By Cheryl Hartfield, Marcus Kaestner, Sascha Mueller, Juan Atkinson-Mora, Ingo Schulmeyer
[ZEISS Semiconductor Manufacturing Technology, Process Control Solutions]
S emiconductor packaging plays a 300mm wafers with submicron accuracies laser integrated with a focused ion beam

key role in the relentless pursuit
companies show hybrid bonding is now
This article details the capability of this
of better electronic system [2]. Recent announcements by multiple scanning electron microscope (FIB-SEM).
performance. Diverse package technologies spreading beyond CMOS imaging sensors new system for microbump analysis of a 3D
and strategies are advancing next- (CIS) into dynamic random access memory stacked-die package.
generation products for smart systems and (DRAM), 2.5D logic, and SoC, with pick
a connected world, and package engineers and place accuracy requirements ranging Package analysis with a laser-
have many options for designing the fullest from 3-5µm down to 250nm, depending on integrated FIB-SEM
functionality into the smallest footprints for application [3]. Some of the most challenging devices
system-in-package (SiP) and system-on- The advances noted above present for characterization are those used in high-
chip (SoC) packages. Recent work shows challenges for package fault isolation, performance computing and artificial
chiplets can be connected to an active process characterization, and failure intelligence, where packages can be 80mm
interposer using 150,000 microbumps at analysis (FA). Design for test (DfT) and in diameter or larger, and the package
20µm pitch in a 40mm x 40mm 3D package FA strategies need to be paired with new interconnect pitches are 40µm and driving
[1]. Additionally, package interconnect analysis tools to enable fast development of smaller [4]. Reconstructed 3D X-ray
dimensions are crossing over into the reliable processes and packages. To achieve microscope (XRM) images show the
space dominated by the silicon back end of rapid analysis of buried fine-pitch package complexity of fine-pitch interconnects in
line (BEOL) dimensions. Hybrid bonding and silicon interconnects, a new approach these devices, which becomes evident at
produces some of the smallest package for high-resolution cross-sectional imaging successively higher resolutions (Figure 1).
interconnects. Submicron pitches have been of structures in 3D packages has been The XRM images are from a delidded,
demonstrated, as well as the bonding of developed. It leverages a femtosecond (fs) but otherwise fully intact, 55mm x

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