Semiconductor Failure Analysis Research Articles

Analysis of Electronic Devices with a Three-Dimensional Atom Probe

Abstract This article discusses the basic procedures involved in atom probe tomography (APT) and demonstrates its use on complex material stacks. Although still a relatively new technique, APT has moved to the forefront of semiconductor failure analysis because it can provide 3D chemical composition of a wide range of materials on a near-atomic scale.

Varnish microlaminations: new insights from focused ion beam preparation

The cross-sectional texture of rock varnish varies considerably with the scale of analysis and technique used to image a sample. Each jump in resolution results in new insight, with the current state-of-the-art resting at the nanoscale. One key to nanoscale analysis involves focused ion beam (FIB) techniques used most frequently in material science and semiconductor failure analysis. FIB preparation remains challenging, however, for samples like rock coatings with heterogeneous density and abundant porosity. A new technique involving multiangle ion thinning and in situ plan-view lift-out facilitated a scanning transmission electron microscopy study of rock varnish from Death Valley. The results reveal variability in lateral continuity of nanometer microlaminae that can be interrupted by post-depositional diagenesis involving leaching of Mn and Fe, and this variability could explain why some of the visual varnish microlaminations (VML) used in paleoclimatic research can sometimes appear discontinuous. Because these breaks result from post-depositional processes, they do not undermine the paleoclimatic interpretations of VML.

Failure Analysis Trends

Abstract Reflecting back on the past 45 years in semiconductor failure analysis, the columnist notes that the trend lines have deviated little over that time. He then goes on to point out the relatively few discontinuities, the latest of which, the emergence of the “invisible defect,” takes him back to the beginning of his journey.

Calibrated nanoscale dopant profiling using a scanning microwave microscope

The scanning microwave microscope is used for calibrated capacitance spectroscopy and spatially resolved dopant profiling measurements. It consists of an atomic force microscope combined with a vector network analyzer operating between 1–20 GHz. On silicon semiconductor calibration samples with doping concentrations ranging from 1015 to 1020 atoms/cm3, calibrated capacitance-voltage curves as well as derivative dC/dV curves were acquired. The change of the capacitance and the dC/dV signal is directly related to the dopant concentration allowing for quantitative dopant profiling. The method was tested on various samples with known dopant concentration and the resolution of dopant profiling determined to 20% while the absolute accuracy is within an order of magnitude. Using a modeling approach the dopant profiling calibration curves were analyzed with respect to varying tip diameter and oxide thickness allowing for improvements of the calibration accuracy. Bipolar samples were investigated and nano-scale defect structures and p-n junction interfaces imaged showing potential applications for the study of semiconductor device performance and failure analysis.

Nanomachining with a focused neon beam: A preliminary investigation for semiconductor circuit editing and failure analysis

As the semiconductor device scaling trend continues, advancement in both focused ion beam source development and application innovations are needed to retain failure analysis and nanomachining application capabilities. In this work, a neon gas field ionization source was studied for its nanomachining properties. The authors have analyzed neon’s nanomachining precision at 10 and 20 keV on blank Cu and SiO2 thin films. Subsurface material amorphization from neon and its correlation with beam current distribution are characterized by TEM. In addition, some preliminary nanomachining work was performed on a 32 nm test chip and successfully demonstrated end-pointing on various device layers.

Laser Voltage Imaging: Setting a New Baseline for Circuit Analysis

Abstract Laser voltage imaging (LVI) enables the global visualization of on-chip circuit activity for the purpose of localizing defects. In a manner reminiscent of e-beam voltage contrast, it allows analysts to visually trace signals through circuit logic in order to see where faults occur. This article explains how laser voltage imaging works and how it is being used in semiconductor failure analysis. It also describes the types of applications for which LVI is not well suited.

Failure localization with active and passive voltage contrast in FIB and SEM

The common Passive Voltage Contrast localization method in Focused Ion Beams and Scanning Electron Microscopes can be used for failure localization issues. These methods became widely accepted in the semiconductor failure analysis community. Nearly all labs make use of it. The Active Voltage Contrast method works with additional external voltages applied inside the chamber to certain structures at the sample surface and offers even more localization possibilities. A comprehensive overview over all phenomena related to Voltage Contrast generation is given and the multiple advantages, possibilities and limits of VC failure localization are systemized and discussed.

Commentary on Applications of EDS in Silicon IC Manufacturing and Failure Analysis

Abstract This article provides a practical overview of energy-dispersive spectroscopy (EDS) and its various uses in semiconductor device manufacturing and failure analysis. It explains how EDS techniques are typically implemented, compares and contrasts different methods, and discusses the factors that determine spatial and energy resolution, measurement depth, sensitivity, signal-to-noise ratio, and ease of use.

Nanoscale Non-Destructive Semiconductor Dopant Characterization and Failure Analysis

The non-destructive semiconductor dopant characterization and failure analysis has been an important and elusive measurement challenge to date. We have employed the vector network analyzer (VNA) as the measurement engine to address the nano scale electronic characterization challenge. The VNA architecture as it exists today has the ability to measure impedances close to the analyzer's own characteristic impedance (i.e., 50 ohms) with good precision up to 100GHz stimulus frequency. However, the measurement precision and resolution provided by a VNA drop by two orders of magnitude as impedance deviates from 50 ohms. We propose a solution that remedies the lack of measurement precision and resolution for large and small impedances when measured by a VNA. Agilent has developed a new scanning microwave microscope (SMM) mode that utilizes a half-wavelength resonator in conjunction with a diplexer connected to a VNA to perform very sensitive capacitance measurements at the tip of a conductive atomic force microscope (AFM). These measurements are achieved via transformation of the high impedance (i.e., the very small capacitance between the AFM tip/sample to the ground) to 50 ohms (i.e., the measurement system's characteristic impedance) using a half-wavelength resonator and diplexer. We also designed a Dopant Profile Measurement Module as a measurement accessory to the SMM system. This module in conjunction with the VNA /SMM enables the non-destructive semiconductor dopant characterization and failure analysis.

Role of Microscopy in Advanced Semiconductor Failure Analysis

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

ISTFA 2009 Panel Discussion: “The FA Engineer’s Career—Past, Present, and Future. What Does the Future Hold for a Career in This Field?”

Abstract Summary of a panel discussion held at ISTFA 2009 to address the following questions. Where is failure analysis heading as a business? What career options are open to an engineer in this field? How do I demonstrate my value to management? Which skills and knowledge will be needed tomorrow? What can I do to find new employment? Should I start or continue my career in semiconductor failure analysis?

Characterization of Patterned Oxide Buried in Bonded Silicon-on-Insulator Wafers by Near-Infrared Scattering Topography and Microscopy

A patterned oxide buried in bonded silicon-on-insulator (SOI) wafers before thinning has been characterized using a near-infrared scattering topography system. This system has been combined with transmission and reflection microscopy. The edge of the patterned oxide buried in the SOI wafer has been observed. Micron-scaled oxide disks formed by the focused ion beam technique in stacked SOI structures have been observed by near-infrared scattering topography. A particle has been identified to be located inside a silicon/air/silicon structure by both near-infrared and visible laser scattering topographies. The size of the particle inside the silicon/air/silicon structure has been estimated to be 0.2 µm from the intensity of scattered near-infrared light. This method has an advantage over semiconductor failure analysis in future scaled-down technologies.

Resolution improvement of acoustic microimaging by continuous wavelet transform for semiconductor inspection

Acoustic microimaging (AMI) is used as an important non-destructive tool in semiconductor reliability evaluation and failure analysis. As advanced microelectronic packages are being produced smaller and thinner, detection of the internal features and defects in the packages is approaching the resolution limits for conventional AMI. To meet this challenge, an acoustic time–frequency domain imaging technique is proposed in this paper, which utilizes the excellent time–frequency localization characteristics of the continuous wavelet transform (CWT) to improve the axial resolution of AMI, without increasing acoustic frequencies. The proposed technique is compared to time domain AMI, frequency domain AMI and sparse signal representation based AMI (SSRAMI) with respect to both axial resolution and robustness. Simulation results show that the proposed technique has superior performance compared to time domain and frequency domain AMI techniques, and has close performance to SSRAMI but with less computation load.

AFM-based scanning capacitance techniques for deep sub-micron semiconductor failure analysis

In this study diffusion areas and junctions of semiconductor structures have been analyzed by Atomic Force Microscopy (AFM) - techniques such as Scanning Capacitance Microscopy (SCM), Scanning Capacitance Spectroscopy (SCS), High Speed Scanning Capacitance Spectroscopy (HSSCS) and Differential Scanning Capacitance Spectroscopy (DSCS). The experimental setups are explained and the measurement procedures are described. Beginning with basic sample preparation techniques, cases studies are presented and advantages and disadvantages of the different techniques are discussed.

Nanoelectronics Failure Analysis

Abstract This article discusses the emergence of nanoelectronics and the effect it may have on semiconductor testing and failure analysis. It describes the different types of quantum effect and molecular electronic devices that have been produced, explaining how they are made, how they work, and the changes that may be required to manufacture and test these devices at scale.

Wavelet analysis based deconvolution to improve the resolution of scanning acoustic microscope images for the inspection of thin die layer in semiconductor

Scanning acoustic microscopy (SAM) is used as an important non-destructive test tool in semiconductor reliability evaluation and failure analysis. However, inspection of thin die layer has proven difficult as the reflected signals from the die top and bottom are superimposed. Conventional deconvolution techniques have been used for the improvement of time resolution in A-scan signal, however, they are not effective for SAM signal because the waveform of the reflected echo is quite different from the incident waveform due to the frequency dependent attenuation and the focal effect. In this paper, in order to overcome this difficulty, a new signal processing method, wavelet analysis based deconvolution technique is proposed. Its validity is approved by computer simulations and practical performances are demonstrated by experiments for the fabricated semiconductor sample.

Electrical characteristics measurement of transistors by 4 tips-0.2 micron probing technique in Semiconductor Failure Analysis

Electrical characteristics measurement of transistors by 4 tips-0.2 micron probing technique in Semiconductor Failure Analysis

Application of Scanning Probe Microscopy techniques in Semiconductor Failure Analysis

Application of Scanning Probe Microscopy techniques in Semiconductor Failure Analysis

Scanning probe microscopy in semiconductor failure analysis

Scanning probe microscopy (SPM) is still a relatively new tool in semiconductor failure analysis (FA). But within the last few years it has developed into an essential imaging method for process control and failure analysis due to its unique features and high adaptability. Atomic force microscopy is indispensable whenever three-dimensional and quantitative surface information combined with unsurpassed resolution is needed. New electrical SPM techniques offer previously inaccessible insights into the nanoscopic construction of semiconductors. They provide for the first time two-dimensional maps of various physical parameters like oxide thickness, doping, temperature or current at sub-micron to nanometer resolution. By this SPM greatly enhances the possibilities of FA to find faults and control processes.

X-Ray Microanalysis in the Environmental SEM Using Mapping and Fourier Deconvolution Techniques

X-ray microanalysis of any type of specimen in its natural state without the use of conventional SEM specimen preparation techniques has immense potential in a wide range of scientific and industrial applications. This capability would be particularly useful in microanalysis applications where it is highly desirable to preserve the integrity of the specimen, for example in semiconductor failure analysis and forensic investigations. in principle, this X-ray microanalysis goal can be achieved in an environmental or variable pressure scanning electron microscope (VPSEM) because specimen charging and vacuum stability problems are negated by the presence of a gas in the specimen chamber. However, the accuracy and spatial resolution of X-ray microanalysis in the VPSEM is significantly degraded by the chamber gas as it scatters primary beam electrons, generating spurious X-rays far from the analysis point. to date, two different X-ray measurement strategies have been developed to facilitate X-ray microanalysis at high chamber pressure in the VPSEM.