Non-Destructive Top Layer Bond Pad Cross Section

2013 ◽  
Vol 2013 (1) ◽  
pp. 000303-000311
Author(s):  
Terence Q. Collier ◽  
Indira Gubeljic
Keyword(s):  
Cross Section ◽  
Thermal Processing ◽  
Quick Response ◽  
Cross Sectional ◽  
Layer Analysis ◽  
Target Layer ◽  
Bond Pads ◽  
Sectional Analysis ◽  
Non Destructive ◽  
Oxidation And Corrosion

Contaminated and corroded aluminum bond pads can lead to a number of reliability failures. Poor wirebondability, false failures at electrical probe due to high contact resistance, opens on RDL layers due to incomplete sputter, and various early life failures during JEDEC testing can all be attributed to excess oxidation and corrosion on aluminum bond pads. Understanding what layers exist on the bond pad surface is critical. Oxides, hydrates, xyfluorides and various soups of materials can be confirmed from combinations of Auger, SIMMS and FTIR but there is a chance the die can be damaged and the spot sizes can be problematic picking up information outside the bond pad target. Layer analysis of the pad can also be difficult since sputtering rates vary based on the contaminants on the pad and any thermal processing. How does one evaluate bond pads without a destructive test? Is there a process for accurate bond pad evaluation while minimizing die damage? Sure. The cycle time and costs of these tests can also be a concern particularly for a customer wanting a quick response from failure analysis. A better method is to bond the die with a gold stud bump followed by selectively etching away the gold. Etching the gold highlights the intermetallics and shows how much of the gold alloyed with aluminum versus blocked oxides. Voiding can be demonstrated, that might be misconstrued as Kirkendall voiding, by cross sectional analysis.

scholarly journals Cross-Sectional Analysis of the Resistance of Rc Members Subjected to Bending With/without Axial Force

2021 ◽  
Author(s):  
Marek Lechman
Keyword(s):  
Cross Section ◽  
Axial Force ◽  
Rectangular Cross Section ◽  
Bending Moment ◽  
Equilibrium Equations ◽  
Cross Sectional ◽  
Cross Sectional Analysis ◽  
Nonlinear Stress ◽  
The Cross ◽  
Sectional Analysis

The paper presents section models for analysis of the resistance of RC members subjected to bending moment with or without axial force. To determine the section resistance the nonlinear stress-strain relationship for concrete in compression is assumed, taking into account the concrete softening. It adequately describes the behavior of RC members up to failure. For the reinforcing steel linear elastic-ideal plastic model is applied. For the ring cross-section subjected to bending with axial force the normalized resistances are derived in the analytical form by integrating the cross-sectional equilibrium equations. They are presented in the form of interaction diagrams and compared with the results obtained by testing conducted on RC columns under eccentric compression. Furthermore, the ultimate normalized bending moment has been derived for the rectangular cross-section subjected to bending without axial force. It was applied in the cross-sectional analysis of steel and concrete composite beams, named BH beams, consisting of the RC rectangular core placed inside a reversed TT welded profile. The comparisons made indicated good agreements between the proposed section models and experimental results.

Failure Analysis of a Qualification Unit Injector for a Satellite Thruster

1998 ◽  
Author(s):  
M. Lipschutz ◽  
R. Brannam ◽  
T. Nguyentat
Keyword(s):  
Failure Analysis ◽  
Cross Section ◽  
Combustion Products ◽  
Design Parameters ◽  
Cross Sectional ◽  
X Ray ◽  
Root Cause ◽  
Qualification Testing ◽  
Non Destructive ◽  
Unit Injector

Abstract This article details the results of a failure analysis performed on a Qualification Unit injector for a military satellite thrusters and explains that the failure was initially detected due to a shift in performance during qualification testing. Failure analysis involved non-destructive evaluation on the injector using micro-focus X-ray and scanning electron microscopy. Serial cross-sectional metallography was then performed, with each cross-section documented by optical microscopy and SEM. The failure analysis resulted in three main conclusions: (1) the root cause of the failure was attributed to multiple detonations in or around the damaged orifice; these detonations were likely caused by fuel and/or combustion products condensing in the orifice between pulses and then igniting during a subsequent pulse; (2) multiple damage mechanisms were identified in addition to the ZOT detonations; and (3) the material and platelet manufacturing process met all design parameters.

Development of DPA (Destructive Physical Analysis) Method for Cu Wire Device

2014 ◽  
Author(s):  
Hirohumi Tateyama ◽  
Wataru Shimizu ◽  
Hidehisa Kubota ◽  
Daisuke Murahara ◽  
Tamiko Hattori ◽  
...  
Keyword(s):  
Cross Section ◽  
Current Method ◽  
Alloy Layer ◽  
Strength Test ◽  
Physical Analysis ◽  
Assembly Process ◽  
Analysis Method ◽  
Cross Sectional ◽  
Reliability Level ◽  
Non Destructive

Abstract Destructive physical analysis (DPA) is one of the reliability evaluation methods, which observes defects and faults in a device, and it can classify the reliability level of the device. After a description of the current method for Au wires, this paper explains the DPA for a Cu wire device. The DPA for semiconductor devices is divided roughly into three steps: a non-destructive inspection, an assembly process inspection, and a wafer process inspection. Investigation of DPA for Cu wire device includes wire material identification, optimization of decapsulation for Cu wire device and wire pull strength test, and observation of package cross-section. From the result, novel sample preparation (embedding a sample in molding package and forming the package to be suitable for cross-sectional observation by ion polishing) enables the observation of the thin alloy layer at the wire/pad interface.

Observation of the Full Interface of Multi-level Interconnects for Sub-Half-Micron Devices

1996 ◽  
Vol 446 ◽  
Author(s):  
Y. Hirose ◽  
T. Katayama ◽  
N. Fujiki ◽  
T. Ohno ◽  
M. Sekine ◽  
...  
Keyword(s):  
Cross Section ◽  
Electrical Resistance ◽  
Interface Layer ◽  
Two Dimensions ◽  
Two Dimensional ◽  
Cross Sectional ◽  
Present Technique ◽  
Multi Level ◽  
Observation Method ◽  
Sectional Analysis

1. AbstractIn recent years, the problem of electrical resistance of vias and contact holes has become greater because a thin insulated layer formed at the interface of the hole has become a serious difficulty in the manufacture of ULSIs. In using conventional techniques of cross sectional analysis to examine the cause, only one cross section of the hole can be analyzed, therefore there is the problem that the two-dimensional interface layer formed cannot be analyzed exactly.In this paper, we have developed a new observation method to inspect two dimensions of the layer formed locally at the interface of the holes. This new observation method gives the configuration, coverage, and element map of the interface layer because the full interface of holes can be inspected; therefore, the process margin can be discussed. The present technique is demonstrated in failure analysis of sub-half-micron vias filled with tungsten.

Cross-section tables of enterprise duration in Łódzkie voivodship

2019 ◽  
Vol 64 (2) ◽  
pp. 17-43
Author(s):  
Artur Mikulec
Keyword(s):  
Cross Section ◽  
Survival Probability ◽  
Cross Sectional ◽  
Strong Similarity ◽  
The Third ◽  
Cross Sectional Analysis ◽  
Sectional Analysis

The aim of the article is to discuss the method of constructing cross-section tables and to present the results of cross-sectional analysis of enterprise duration in Łódzkie voivodship in the years 2001—2015 (including cities with powiat status such as Łódź, Piotrków Trybunalski and Skierniewice). The analysis was conducted on the basis of data derived from the National Official Business Register REGON. The article with selected annual information from cross-sectional enterprise duration tables prepared for enterprises liquidated in Łódzkie voivodship contains i.a., assessment of liquidation survival probability of enterprises in the first, third and fifth year before liquidation, and estimation of the probability of persistence and survival in the period 0—1, 0—3 and 0—5 years before liquidation.The obtained results confirmed that in each of the analysed periods there was a strong similarity in characteristics of enterprise duration in Łódzkie voivodship, including Łódź. However, the situation of enterprises from Piotrków Trybunalski and Skierniewice differed in terms of duration from the situation of units from Łódź, particularly for the third year before liquidation.

scholarly journals Prognostic Value of Ambulatory Blood Pressure Load in Pediatric CKD

2020 ◽  
Vol 15 (4) ◽  
pp. 493-500
Author(s):  
Jason Lee ◽  
Charles E. McCulloch ◽  
Joseph T. Flynn ◽  
Joshua Samuels ◽  
Bradley A. Warady ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Cross Section ◽  
Odds Ratio ◽  
Prognostic Value ◽  
Ventricular Hypertrophy ◽  
Left Ventricular ◽  
Adverse Outcomes ◽  
Cross Sectional ◽  
Pediatric Ckd ◽  
Sectional Analysis

Background and objectivesElevated BP load is part of the criteria for ambulatory hypertension in pediatric but not adult guidelines. Our objectives were to determine the prevalence of isolated BP load elevation and associated risk with adverse outcomes in children with CKD, and to ascertain whether BP load offers risk discrimination independently or in conjunction with mean ambulatory BPs.Design, setting, participants, & measurementsWe studied 533 children in the CKD in Children (CKiD) Study to determine the prevalence of normotension, isolated BP load elevation (≥25% of all readings elevated but mean BP normal), and ambulatory hypertension. We examined the association between these categories of BP control and adverse outcomes (left ventricular hypertrophy [LVH] or ESKD). We used c-statistics to determine risk discrimination for outcomes by BP load used either independently or in conjunction with other BP parameters.ResultsOverall, 23% of the cohort had isolated BP load elevation, but isolated BP load elevation was not statistically significantly associated with LVH in cross-section (odds ratio, 1.8; 95% CI, 0.8 to 4.2) or time to ESKD (hazard ratio, 1.2; 95% CI, 0.7 to 2.0). In unadjusted cross-sectional analysis, every 10% higher systolic BP load was associated with 1.1-times higher odds of LVH (95% CI, 1.0 to 1.3), but discrimination for LVH was poor (c=0.61). In unadjusted longitudinal analysis, every 10% higher systolic BP load was associated with a 1.2-times higher risk of ESKD (95% CI, 1.1 to 1.2), but discrimination for ESKD was also poor (c=0.60). After accounting for mean systolic BP, systolic BP load was not statistically significantly associated with either LVH or ESKD. Findings were similar with diastolic BP load.ConclusionsBP load does not provide additive value in discriminating outcomes when used independently or in conjunction with mean systolic BP in children with CKD.PodcastThis article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2020_03_11_CPOD10130819.mp3

Asymptotic Approach to Oblique Cross-Sectional Analysis of Beams

2013 ◽  
Vol 81 (3) ◽  
Author(s):  
Anurag Rajagopal ◽  
Dewey H. Hodges
Keyword(s):  
Cross Section ◽  
Ad Hoc ◽  
Beam Theory ◽  
Reference Line ◽  
Cross Sectional ◽  
Cross Sectional Analysis ◽  
Variational Asymptotic ◽  
Validation Set ◽  
3D Elasticity ◽  
Sectional Analysis

Structural and aeroelastic analyses using beam theories by default choose a cross section that is perpendicular to the reference line. In several cases, such as swept wings with high AR, a beam theory that allows for the choice of a cross section that is oblique to the reference line may be more convenient. This work uses the variational asymptotic method (VAM) to develop such a beam theory. The problems addressed are the planar deformation of a strip and the full 3D deformation of a solid, prismatic, right-circular cylinder, both made of homogeneous, isotropic material. The motivation for choosing these problems is primarily the existence of 3D elasticity solutions, which comprise a complete validation set for all possible deformations and which are shown to be accurately captured by the current analysis. A secondary motivation was that the development and final results of the beam theory, i.e., the cross-sectional stiffness matrix and stress-strain-displacement recovery relations, are obtainable as closed-form analytical expressions. These results, coupled with the VAM-based beam analysis being devoid of ad hoc assumptions, culminate in what is expected to be of significance when formulating a general oblique cross-sectional analysis for beams with anisotropic material and initial curvature/twist, the detailed treatment of which will be alluded to in a later paper.

scholarly journals Efficient Fatigue Analysis of Helix Elements in Umbilicals and Flexible Risers: Theory and Applications

2012 ◽  
Vol 2012 ◽  
pp. 1-22 ◽  
Author(s):  
Geir Skeie ◽  
Nils Sødahl ◽  
Oddrun Steinkjer
Keyword(s):  
Cross Section ◽  
Fatigue Analysis ◽  
Special Importance ◽  
Stress Cycle ◽  
Cross Sectional ◽  
Stick Slip ◽  
Cross Sectional Analysis ◽  
Analysis Scheme ◽  
Sectional Analysis

Fatigue analysis of structural components such as helix tensile armors and steel tubes is a critical design issue for dynamic umbilicals and flexible pipes. The basis for assessment of fatigue damage of such elements is the long-term stress cycle distribution at critical locations on the helix elements caused by long-term environmental loading on the system. The long-term stress cycle distribution will hence require global dynamic time domain analysis followed by a detailed cross-sectional analysis in a large number of irregular sea states. An overall computational consistent and efficient fatigue analysis scheme is outlined with due regard of the cross-sectional analysis technique required for fatigue stress calculation with particular attention to the helix elements. The global cross-section is exposed to pure bending, tensile, torsion, and pressure loading. The state of the different cross-section elements is based on the global response. Special emphasis is placed on assessment of friction stresses caused by the stick-slip behavior of helix elements in bending that are of special importance for fatigue life assessments. The described cross-sectional analysis techniques are based on an extensive literature survey and are hence considered to represent industry consensus. The performance of the described calculation scheme is illustrated by case studies.

Mass Determination by Direct Measurement of Electron Scattering

1975 ◽  
Vol 33 ◽  
pp. 240-241
Author(s):  
M. K. Lamvik ◽  
A. V. Crewe
Keyword(s):  
Cross Section ◽  
Electron Scattering ◽  
Mass Density ◽  
Variable Mass ◽  
Scattering Cross Section ◽  
Mass Determination ◽  
Number Density ◽  
Cross Sectional ◽  
Thin Slice ◽  
Scattering Cross

If a molecule or atom of material has molecular weight A, the number density of such units is given by n=Nρ/A, where N is Avogadro's number and ρ is the mass density of the material. The amount of scattering from each unit can be written by assigning an imaginary cross-sectional area σ to each unit. If the current I0 is incident on a thin slice of material of thickness z and the current I remains unscattered, then the scattering cross-section σ is defined by I=IOnσz. For a specimen that is not thin, the definition must be applied to each imaginary thin slice and the result I/I0 =exp(-nσz) is obtained by integrating over the whole thickness. It is useful to separate the variable mass-thickness w=ρz from the other factors to yield I/I0 =exp(-sw), where s=Nσ/A is the scattering cross-section per unit mass.

A tilting high temperature gas reaction chamber for the JEM 7A T.E.M.

1978 ◽  
Vol 36 (1) ◽  
pp. 70-71
Author(s):  
Brian L. Rhoades
Keyword(s):  
Cross Section ◽  
Reaction Chamber ◽  
Objective Lens ◽  
Reduced Cross Section ◽  
Cross Sectional ◽  
Structural Investigations ◽  
Transmission Electron ◽  
Dynamic Experiments ◽  
Successful Design ◽  
Thermocouple Junction

A gas reaction chamber has been designed and constructed for the JEM 7A transmission electron microscope which is based on a notably successful design by Hashimoto et. al. but which provides specimen tilting facilities of ± 15° aboutany axis in the plane of the specimen.It has been difficult to provide tilting facilities on environmental chambers for 100 kV microscopes owing to the fundamental lack of available space within the objective lens and the scope of structural investigations possible during dynamic experiments has been limited with previous specimen chambers not possessing this facility.A cross sectional diagram of the specimen chamber is shown in figure 1. The specimen is placed on a platinum ribbon which is mounted on a mica ring of the type shown in figure 2. The ribbon is heated by direct current, and a thermocouple junction spot welded to the section of the ribbon of reduced cross section enables temperature measurement at the point where localised heating occurs.

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