In DRAM devices, many failures only appeared in a specific operating state on chips during functional tests. Dynamic photon emission microscopy (D-PEM) is a useful technique in failure analysis for emitted photons when the device under test (DUT) is electrically exercised. Therefore, D-PEM analysis combined with specific external triggers in functional test can activate the chip, and thereby expand the range of detectable defects and increase the chances of finding a specific failure mode. In this study, we will discuss various cases of external triggers applied from the tester. This method can be used to detect emission which did not show up in conventional test condition in PEM method for localizing active fails in DRAM. Then, after localizing the site of failure, more detailed physical visualization by Focused Ion Beam (FIB) cross section image, Transmission Electron Microscope (TEM), and Energy Dispersive X-ray microscopy (EDX) revealed main causes of failure. We believe that our method could be a future solution for increasingly difficult and diverse failures modes in the DRAM industry.

In the field of failure analysis (FA) for semiconductor devices, the transmission electron microscope (TEM) as an analytical tool is integral to finding visible evidence of defects and their root cause. Especially as device features shrink, imaging and analyzing increasingly subtle defects requires detailed elemental analysis. In this work, elemental analysis using an aberration-corrected TEM at different accelerating voltages (200 kV and 80 kV) is discussed. The impact of accelerating voltage on elemental analysis with regards to Electron Energy Loss Spectroscopy (EELS) and Energy Dispersive X-Ray Spectroscopy (EDS) is of central focus. Two case studies involving TEM samples of different thicknesses are presented that clearly indicate important differences in the analytical data collected at different accelerating voltages. The work revealed that for elemental analysis of thick TEM samples (100 nm and over) 200 kV is preferred, and for thin samples, 80 kV provides superior signal in EDS and EELS.

This study investigates the application of 3D electron tomography to enhance transmission electron microscopy (TEM)-based failure analysis of 3D FinFET transistors. Traditional TEM analysis is challenged by projection effects due to the thickness of the sample, complicating accurate defect characterization in miniaturized semiconductor structures. The defects seen by conventional (2D projection) TEM imaging are unclear and difficult to interpret. Leveraging scanning transmission electron microscopy (STEM) and energy dispersive X-ray spectroscopy (EDS) tomography techniques, the study presents detailed examinations of two semiconductor samples exhibiting high leakage currents. Results reveal etched-out epitaxial regions subsequently filled with gate materials, critical for understanding device failure. By digitally reconstructing TEM lamellae in three dimensions, this approach overcomes projection artifacts and precisely localizes defects. The findings underscore the efficacy of 3D electron tomography in semiconductor failure analysis, offering insights crucial for improving device reliability and manufacturing processes in advanced semiconductor technologies.

Power MOSFETs are electronic devices that are commonly used as switches or amplifiers in power electronics applications such as motor control, audio amplifiers, power supplies and illumination systems. During the fabrication process, impurities such as copper can become incorporated into the device structure, giving rise to defects in crystal lattice and creating localized areas of high resistance or conductivity. In this work we present a multiscale and multimodal correlative microscopy workflow for the characterization of copper inclusions found in the epitaxial layer in power MOSFETs combining Light Microscopy (LM), non-destructive 3D X-ray Microscopy (XRM), Focused-Ion Beam Scanning Electron Microscopy (FIB-SEM) tomography coupled with Energy Dispersive X-ray Spectroscopy (EDX), and Transmission Electron Microscopy (TEM) coupled with Electron Energy Loss Spectroscopy (EELS). Thanks to this approach of correlating 2D and 3D morphological insights with chemical information, a comprehensive and multiscale understanding of copper segregations distribution and effects at the structural level of the power MOSFETs can be achieved.

For device qualification in harsh environments (space, avionic and nuclear), radiation testing identifies the sensitivity of the devices and technologies and allows to predict their degradation in these environments. In this paper, the analysis of the electrical characteristics and of the failure of a commercial SiC MOSFET after a Single Event Burnout (SEB) induced by proton irradiation are presented. The goal is to highlight the SEB degradation mechanism at the device and die levels. For failed devices, the current as a function of the drain-source bias (VDS) in off-state (VGS=0V) confirms the gate rupture. For the die analysis, Scanning Electron Microscopy (SEM) investigations with energy-dispersive X-ray spectroscopy (EDX) analysis reveals the trace of the micro-explosion related to the catastrophic SEB inside the SiC die. With a fire examination, similar to a blast, the SEM analysis discloses damages due to the large local increase of the temperature during the SEB thermal runaway, leading to the thermal decomposition of a part of the SiC MOSFET and the combustion with gaseous emissions in the device structure.

In this work we have investigated the results obtained using fault isolation techniques such as EMMI, OBIRCH and OBIC on a Wide band gap power device and in particular a 4H-SiC. We used YLF laser and Green Laser and showed the differences in the resulting hot spots. In the selected point, FIB cross sectioning and EDS analysis was performed. Once that the defect was shown, the differences the fault isolation results were discussed.

In this work, we investigate mushroom type phase-change material (PCM) memory cells based on Ge 2 Sb 2 Te 5 . We use low-angle annular dark field (LAADF) STEM imaging and energy dispersive X-ray spectroscopy (EDX) to study changes in microstructure and elemental distributions in the PCM cells before and after SET and RESET conditions. We describe the microscope settings required to reveal the amorphous dome in the RESET state and present an application example involving the failure analysis of a PCM test array made with devices fabricated at IBM’s Albany AI Hardware Research Center.

This paper presents a failure analysis to determine the origin of the failure on the soldered balls of one BGA soldered to a Printed circuit board, presenting Intermittency on the soldered joints, by Visual inspection, X ray inspection, Computed Tomography(CT), Cross-section analysis, Scanning Electron Microscopy, and Energy dispersive spectroscopy, determined the failure located on soldered balls of the BGA was caused by cracks that run along the Intermetallic layer formed between the solder balls and the copper pads of the printed circuit board, that were located near the BGA corners. With X ray computed Tomography we can analyze all the soldered balls of the BGA, by "virtual" cross-sections on the soldered joints without damage on the sample.

The continuously growing demands in high-density memories drive the rapid development of advanced memory technologies. In this work, we investigate the HfOx-based resistive switching memory (ReRAM) stack structure at nanoscale by high resolution TEM (HRTEM) and energy dispersive X-ray spectroscopy (EDX) before and after the forming process. Two identical ReRAM devices under different electrical test conditions are investigated. For the ReRAM device tested under a regular voltage bias, material redistribution and better bottom electrode contact are observed. In contrast, for the ReRAM device tested under an opposite voltage bias, different microstructure change occurs. Finite element simulations are performed to study the temperature distributions of the ReRAM cell with filaments formed at various locations relative to the bottom electrode. The applied electric field as well as the thermal heat are the driving forces for the microstructure and chemical modifications of the bottom electrode in ReRAM deceives.

The composition of InGaN/AlN/GaN MQWs nano structure is anlayzed by STEM/EDS. The concentration of nitrogen in GaN materials is usually lower than that of gallium for specimen thickness larger than 50 nm due to low penetration ability of N K X-rays (0.392 KeV). The concentration of indium in the InGaN quanturm wells obtained by STEM/EDS analysis is always much lower its real value. This concentration dilution in this 3 nm structure results from the effect of electron beam broadening, and can be improved to a certain level by reducing specimen thickness, C2 aperture, and dwell time, with a sacrifice in signal intensity.

In semiconductor manufacturing technology, copper has been widely used for BEOL process due to better conductivity than aluminum. TEM (Transmission Electron Microscopy) characterization has been played in key role to understand the process of semiconductor manufacturing. Gallium base Focused Ion Beam (FIB) is widely used on TEM sample preparation. The experiment to understand the impact of gallium which is from sample preparation process on Cu layer was performed. In-situ TEM studies have shown real time material characteristic of Cu at various temperature [1]. We observed the gallium aggregation phenomenon on Cu layer at round the temperature of 400°C. This thermal aggregation of gallium on Cu layer has been confirmed by EDS analysis in the study. Detectable amount of gallium was found in whole area in the sample before heating the sample at in-situ TEM work. This paper also introduces alternative solutions to resolve this gallium aggregation in copper layer including the sample preparation technique using Xe Plasma Focused Ion Beam (PFIB) [2]. This Xe PFIB showed the substantial improvement of specimen quality for the in-situ TEM experiment of sample preparation.

Lock-in thermography (LIT) has been successfully applied in different excitation and analysis modes including classical LIT, analysis of the time-resolved temperature response (TRTR) upon square wave excitation and TRTR analysis in combination with arbitrary waveform stimulation. The results obtained by both classical square wave- and arbitrary waveform stimulation showed excellent agreement. Phase and amplitudes values extracted by classical LIT analysis and by Fourier analysis of the time resolved temperature response also coincided, as expected from the underlying system theory. In addition to a conceptual test vehicle represented by a point-shaped thermal source, two semiconductor packages with actual defects were studied and the obtained results are presented herein. The benefit of multi-parametric imaging for identification of a defect’s lateral position in the presence of multiple hot spots was also demonstrated. For axial localization, the phase shift values have been extracted as a function of frequency [4]. For comparative validation, LIT analyses were conducted in both square wave and arbitrary waveform excitation using custom designed and sample-specific stimulation signals. In both cases result verification was performed employing X-ray, scanning electron microscopy (SEM) and energy dispersive x-ray (EDX) as complementary techniques.

The potential benefits and challenges of low kV SEM imaging and EDS elemental analysis have been discussed in the SEM community since at least the early 1990s [1,2]. Concurrent with steady progress in the performance of so-called extreme high-resolution ‘XHR’ SEM imaging [3], is an advancement in low-energy EDS using windowless, large solid angle ‘racetrack’ EDS detectors [4]. As lower kV imaging and EDS analysis becomes accessible, refined models of the interaction of low energy electron beam and real-world samples continues at full speed even today [5].

Reliability tests, such as Time-Dependent Dielectric Breakdown (TDDB), High-Temperature Operating Life (HTOL), Hot Carrier Injection (HCI), etc., is required for the lifetime prediction of an integrated circuit (IC) product. Those reliability tests are more stringent and complex especially for automotive Complementary Metal–Oxide–Semiconductor (CMOS) devices, this because it involves human lives and safety. In foundries failure analysis (FA), Transmission Electron Microscopy (TEM) analysis often required in order to provide insights into the defect mechanisms and the root cause of the reliability tests. In this paper, application of high resolution Nano-probing Electron Beam Absorbance Current (EBAC), Nano-probing active passive voltage contrast (APVC), and TEM with Energy Dispersive X-Ray Spectroscopy (EDX) to identify the failing root cause of Inter- Poly Oxide (IPO) TDDB failure on an automotive grade Non- Volatile Memory (NVM) device was investigated. We have successfully demonstrated that TEM analysis after Nanoprobing EBAC/APVC fault isolation is an effective technique to reveal the failure root cause of IPO breakdown after reliability stresses.

Contamination and particle reduction are critical to semiconductor process control. Lots of failure analysis had been focused on finding the root cause of the particle and contamination. The particle and contamination effect were also easily found in circuit probing (CP) process, and therefore induced yield loss and wafer scrap. In the first part of this paper, an oven contamination case was studied. The second part of this paper focus on oven contamination monitoring. In the beginning, a die flying failure was papered at the stage of blue tape and die sawing. This event clearly indicated bad adhesion between die and plastic tape. This bad adhesion was suspected to be a particle/contamination layer formed on bad die surface. Three failure analysis (FA) approaches were performed to find out the root cause. The SEM/EDS result identified the main elements of big particle, but that is insufficient to identify the root cause. The OM/FTIR, however, showed the contamination may be related to polydimethylsiloxane (PDMS). The last failure analysis was the time of fly Secondary Ion Mass Spectrometer (TOF-SIMS), the result confirmed that there was a thin PDMS layer formed on the contaminated bad die surface. The high temperature CP process induced PDMS is believed to be the contamination root cause. In order to prevent the oven contamination event, a methodology based on contact angle and wettability of Si matrix sample was set up for regular monitor in oven operation. The details of contact angle test (CAT) sample preparation, measurement and analysis results were also discussed in this paper.

The results presented here show how high-speed simultaneous EBSD and EDS can be used to characterize the essential microstructural parameters in SnPb solder joints with high resolution and precision. Analyses of both intact and failed solder joints have been carried out. Regions of strain localization that are not apparent from the Sn and Pb phase distribution are identified in the intact bond, providing key insights into the mechanism of potential bond failure. In addition, EBSD provides a wealth of quantitative detail such as the relationship between parent Sn grain orientations and Pb coarsening, the morphology and distribution of IMCs on a sub-micron scale and accurate grain size information for all phases within the joint. Such analyses enable a better understanding of the microstructural developments leading up to failure, opening up the possibility of improved accelerated thermal cycling (ATC) testing and better quality control.

This paper describes the failure analysis methods used to characterize micro cracks that resulted in laser vias of printed circuit boards (PCBs) through case studies of destructive failure analysis. Defects such as cracks in laser vias of PCBs can cause open or low leakage failure mode of module due to improper cleaning during the PCB process, natural oxide films such as brown oxide, or physical forces by use. Therefore, it’s difficult to identify the causes of these phenomena unless proper analytical techniques are used. In this study, multiple analytical techniques are employed to characterize micro cracks in laser vias. The destructive analysis with cross section and ion milling process is used to detect and inspect an accurate micro crack phenomenon of laser via. The characterization analysis using TEM, EDX and SIMS equipment after separating laser vias from a PCB is used to analyze failure cause of micro crack in laser via. This paper will be concluded with a discussion about what physical analysis methods should be used to analyze the causes of micro cracks for laser vias of PCBs.

In this paper, impact of carbon on threshold voltage in MOSFET-based device is studied by 3D-atom probe tomography (APT). Carbon is one of most difficult contaminants incorporated from fab-environment to be detected by typical analytical techniques such as TEM-EDS or SIMS. Here, we successfully demonstrated the detection of carbon segregated at gate oxide/Si substrate interface using 3D-APT with single-atom sensitivity and sub-nanometer spatial resolution. It was found that the carbon contaminants have significant effect on the threshold voltage shift (ΔVth), in which ΔVth increases slightly with increasing carbon concentration. The deterioration of device performance is explained by means of which the positively ionized carbons at the interface acting as additional positive charges affecting the inversion to n-channel.

The State-of-the-Art FinFET technology has been widely adopted in the industry, typically at 14 nm and below technology nodes. As fin dimensions are pushed into the nanometer scale, process complexity is highly escalated, posing great challenges for physical failure analysis. Meanwhile, the accelerated cycles of learning for new technology nodes demand high accuracy and fast turnaround time to solve the material and interface issues pertaining to semiconductor processing or device failure. In this paper, we report a case study of fin related defect that caused device failure. Several analytical techniques, namely, Scanning Electron Microscopy (SEM), plan-view and cross-section Transmission Electron Microscopy (TEM) with Energy Dispersive X-ray spectroscopy (EDX), Electron Energy Loss Spectroscopy (EELS) and Z-contrast tomography were employed to characterize the defect and identify root-cause, leading to the resolution of this issue.

Device failure analysis typically requires multiple systems for fault identification, preparation and analysis. In this paper we discuss the practicalities and limits of using a single FIBSEM system for a complete failure analysis workflow. The theoretical requirements of using a nanomanipulator for both lamella lift out and electrical testing are discussed and the current capabilities of windowless X-rays detectors for chemical analysis demonstrated. When the required resolution for failure analysis exceed the limits of a FIBSEM and TEM is required, the combination of the nanomanipulator and X-ray detector for advanced lift out and thickness controlled thinning techniques are demonstrated to prepare exceptional quality lamellae.