Effectiveness of Non Destructive Physical Analysis Method Using X-ray CT Imaging

Lettuce are vegetables with a high commercial value and a short cycle production, which requires precise managements to guarantee a profitable production. For this, the nutritional providing is an important factor, highlining the nitrogen, a macronutrient considered essential for the proper development of plants due to its participation in the composition of the main plant molecules, such as chlorophyll. In this sense, non-destructive strategies to monitor the balance nutrition is fundamental to avoid deficiency or excess of nutrients during the lettuce cycling, and the agriculture 4.0, brings to light new technological means to achieve this goal. This work aimed to verify the potential to use a portable spectrophotometer to estimate N shoot in lettuce, as a non-destructive, precise, quickly, cheap, waste free option to be operated by the lettuce farmers, on farm, for the N monitoring, based on the destructive laboratory analysis for N shoot and chlorophyll, and the widely used sensor chlorophyll meter (SPAD). For this, a greenhouse experiment was conducted with lettuce cropped under N levels input, corresponding to 0, 25, 50, 75, 100 and 125% of the lettuce recommendation. The estimation for N in the lettuce shoot was performed by destructive analysis: i) shoot N; ii) chlorophyll and non-destructive analysis: iii) chlorophyll meter SPAD and iv) a portable spectrophotometer. Non-destructive measurements were performed 3 times at: 20, 23 and 26 days after transplanting (DAT). The lettuce harvest occurred 28 DAT, to determine N shoot uptake and chlorophyll, using a destructive way, and lettuce production. The estimation of N shoot in lettuce using the portable spectrophotometer showed a high correlation to the standard destructive laboratory analysis and the chlorophyll meter (SPAD), showing high explanation of the data and so a high potential to estimate N shoot in lettuce using the proposed portable spectrophotometer as an optimum non-destructive, precise, quickly, cheap, waste free option to be operated by the lettuce farmers, on farm, for the N monitoring.

Lithium-ion cell response to mechanical abuse: Three-point bend

The effects of delamination at the mold component/die interface during reliability testing are investigated using scanning acoustic microscopy (SAM), and electrical and physical analyses. The SAM results are correlated with electrical end point (EEP) tests and destructive physical analysis. The spread of delamination during temperature cycling of units is examined. It is demonstrated that scanning acoustic microscopy provides a significant improvement over cross sectioning for the inspection of critical defects in IC packages. The impact of this result on a test method for package reliability evaluation based on inspection for package cracks is discussed. >

Possible approaches for studying three dimensional structure of lignin

Scanning acoustic microcopy (SAM) method with inverted inspection direction has been successfully develop and evaluate the quality of flip chip underfill and interconnect bonds in manufacturing of microelectronic components. Acoustic microscopes utilize high frequency ultrasound transmitting through the silicon chip backside in one scan to access and examine the internal structures in optically opaque materials. These non-destructive methods relatively enable the defect localization which leads microstructural examinations involving destructive analysis sample preparation. For the justification of accuracy of SAM method analysis, a destructive cross-sectioned and mechanical lapping physical analysis were performed for preparing the samples and examine by optical microscope and Scanning Electron Microscope (SEM) for defect verification. Cases studies have been demonstrated that the capabilities of conventional SAM inspection and advantages over other analysis method.

The research ethic in the world limits sampling and destructive analyses as much as possible and accepts only the use of non-destructive techniques to maintain the integrity of the excavation finds. Up to now, the research on Iznik tiles was carried out on a limited number of artifacts with which the researchers were not able to perform any statistical assessment to define different workshops that existed in the excavation area of Iznik Tile Kilns. Moreover, most of the previous studies were concerned with artistic and morphological investigations rather than the analyses of glaze and coloring agents. Since 2018, non-destructive analyses with pXRF and stereo microscope started on the excavation materials to define the glaze, coloring agents, and body composition. Some ceramics and tile sherds were also characterized with a confocal Raman spectrometer in the laboratory to complement the chemical data obtained with pXRF.

A commercial-off-the-shelf (COTS) cylindrical 18650 Li-Ion cells have been proven to be extremely reliable power sources from many electronic applications for long periods and adopted to the EV applications. The cylindrical cells have been considered a reliable power source for the aerospace battery system, thanks to their high energy and power density. However, some electronic applications' field failure histories and some test programs have indicated that batteries built with cylindrical 18650 cells in multi-cell configurations (series and parallel) have experienced safety issues under various test conditions. Another requirement of the aerospace battery is a long-life cycle under harsh operating conditions. A tiny potential risky outlier cell, which cannot be identified and detected during the cell manufacturing process, can severely affect the multi-combination battery system's safety and reliability, like the EV, ESS, and Aerospace battery system. This paper studied a cell selection and screening method and developed a validation process to evaluate the efficiency and reliability of the cell selection and screening process. A cell selection method includes visual inspection, mass and dimension check, some electrical tests (OCV, CCV, AC Impedance), capacity measurement, and cell level safety test according to widely accepted cell safety standards and battery industrial best practices of the lithium-ion battery. The cell screening method and procedure followed the process and criteria on the NASA technical document (Specification for Acceptance Testing Commercial Lithium-Ion Cells). This program adopted the 6-sigma concept on the data analysis of the cell selection and screening process, which rejects the outlier cells of the 3-sigma level of each test item. The validation process was designed with two test conditions: 1) cycle test on the regular operation of the Human-spaceflight's mission operating conditions and 2) accelerate test condition of the maximum (most severe) cycle condition of the cell makers specification document. The regular operation cycle test was designed to evaluate the screening process's efficiency, whether the 3-sigma level screening is acceptable to the performance of the battery system using all passed cell samples from the screening. The regular cycle test selects four types of 4S string battery groups from different combinations of the cell samples. And it was performed according to the Human-spaceflight's mission operating conditions to validate the 4S can meet the required cycle condition. On the other hand, the accelerated cycle test was designed to identify the difference of cell degradation and capacity decay between the two types of cell combinations by the cycle test. One group use cells randomly selected samples from the non-screen cell, and the other group used selected cells from passed group cell as a control sample. Both 4S strings were cycled at the accelerate test condition, the maximum (most severe) cycle condition of the cell makers specification document. The battery capacity decay and the cell's internal resistance changes by DC pulse technics were checked regularly every 100 cycles during the cycle test.The performance of both 4S was almost similar until 200 cycles. However, the non-screen 4S string's capacity decay speed was much faster and reach death after the 500 cycles, while the screened 4S runs without any severe capacity decline until 800 cycles. EIS (Electrochemical Impedance Spectroscopy) technique was applied to each cell of the 4S string. The DPA (destructive Physical Analysis) and electron microscope analysis were used to identify the electrode's degradation degree and study the cell failure mechanism during the accelerated cycle tests. The DPA and electron microscope analysis (SEM-EDS) identified that gradual damage of the cathode electrode material of the non-screened 4S string during the accelerated cycle test was the leading cause of the cell capacity decay. This research discusses that non-screened 4S string may have different characteristic cell among the four cells in the 4 S string compare to the screened 4S string. That can initiate the stress to the cell and then increase the cell internal resistance, following enhanced cell heat generation and eventually getting the cell imbalance. The cell imbalance and heat generation get the cell getting worse after 200 cycles and eventually kill the cell and 4S sting. This research concludes that the used cell screening process is effective and beneficial as a cell screening process for the multi-cell battery system, especially for the long-term cycle-life battery system, like EV, ESS, and aerospace applications. Figure 1

The radionuclide 192Ir has been increasingly used as a brachytherapy source and manufactured in different geometry forms (thin wires, hairpins, needles or point sources). A procedure for the characterization of the activity content of 192Ir wire sources was developed in order to establish the secondary standard activity measurement system based on the ionization chamber set up at Brazilian National Laboratory for Ionizing Radiation Metrology (LNMRI). Firstly, the ion current of the ionization chamber is measured and, subsequently, the activity is determined in a destructive analysis. This procedure enables obtaining the calibration factor for wire sources that can be used for further activity determination of similar sources in a non-destructive analysis. Accurate activity determination is needed for dosimetric measurements and for helping the manufacturers to improve its quality control programs.

A procedure for measuring trace amounts of Li and Be in different types of samples has been studied using a 12.5 MeV14N beam. At this energy the principal nuclear reactions are6Li(14N, d)18F,7Li(14N, t)18F, and9Be(14N, αn)18F. Detection limit for destructive analysis for either beryllium or lithium has been calculated at 300 ppb with a determination limit of 5 ppm for an irradiation with a beam of 1 μA·h/cm2. Destructive analysis was performed on CANMET SY-2 and USGS BCR-1 (rock samples 1–10 ppm Be). Non-destructive analysis for beryllium and lithium was performed on NBS SRM 610 (500 ppm trace element glass), NBS 612 (50 ppm trace element glass), and NBS SRM 181 (Spodumene ore, 6.4% Li2O). Detection limit of 2 ppm has been calculated for nondestructive analysis of either lithium or beryllium.

This article provides a brief review of protocols used in peat inorganic geochemistry. We emphasise the key issues that could lead to inter-comparison problems. For each section (drying, grinding, non-destructive analyses, acid digestions and destructive analyses), recommendations are provided to guide the reader through an idealised protocol, which is the only workable approach for studies incorporating long-term comparisons.

With the modern and advance IC packaging structures introduced to the market now-a-day, the limitation and complication of the signal interpretation of the other nondestructive techniques, such as the scanning acoustic microscope (SAM) method, diminished the capability to identify any micro-crack on the die surface. In addition, the destructive analysis could also introduce the excess forces, which possibly induce the artifact micro-crack after the die is exposed by decapsulation or polishing techniques. Hence, the new non-destructive analysis technique for detecting micro-cracks and crack patterns in the IC memory devices has been proposed. This technique can easily detect the micro-cracks and crack patterns by utilizing the memory tester bitmap feature. The shorter analysis time and higher success rate can be achieved comparing to the other non-destructive techniques.

High voltage Schottky diodes, often used in DC-to-DC converters are susceptible to single event burnout (SEB) due to energetic particle strike, posing a concern for their use in space components. Prior to recent test reports, diode SEB had not been considered a risk to space programs despite the phenomenon having been studied in high power terrestrial PN diodes in the 1990s. Schottky diodes have been engineered to prevent premature breakdown under high reverse bias voltage and minimize leakage currents at the edge of the contact electrode. Graded passivation structures, p+ doped guard rings, and a metallization field plate and thick field oxide help to mitigate failures due to the high electric fields resulting from sharp edge effects at the contact electrode. Recent heavy ion strike data indicates a tendency to failure along the guard ring structure and an effective drop in failure rate of two orders of magnitude has been observed after protective masking of the diode edge that includes this area. Due to the lack of comprehensive test data and understanding of the exact physics of failure, SEB in Schottky diodes has an uncertain impact on reliability. Existing space contractor derating guidelines may already be sufficient to mitigate this failure but with an uncertain margin that could further depend on the diode type, design, and implementation. We investigate the observed preferential SEB through physics-based computer modeling using Silvaco TCAD. We perform transient electro-thermal simulations on three-dimensional structures derived from destructive physical analysis (DPA) of failed diodes and failure sites. This effort should better the understanding of the risk of diode SEB by coupling numerical modeling with direct observations of failure.

The attempt to establish a reliable analysis for Ni(III) in nickel plates obtained during destructive physical analysis (DPA) from both nickel-cadmium and nickel-hydrogen cells has continued. The standard analysis utilizing ground plate material from the positive plates often gives unexpectedly low or even negative results for plates from discharged cells. In a previous paper an alternative procedure was reported. In that method, negative results were eliminated and more reasonable positive analyses were obtained. The work has been extended to analysis of standard materials containing Ni(III) and Ni(IV) where independent verification of those species was possible. The nature of the residual metals contained in the plate material samples has also been identified and quantified. Finally, an analytical method utilizing a basic solution procedure has been evaluated and compared to the standard acidic media procedure. >

The objective of the present study is to evaluate the impact of electronic packaging design/manufacturing process parameters on the thermal fatigue life of ball grid array (BGA) solder joints. The four selected parameters are BGA under-fill materials, conformal coating, solder pad sizes on printed wiring board, and BGA rework, with each having either two or three levels of variation. A test vehicle (TV), on which various sizes of BGA daisy-chained packages are soldered, is first designed and fabricated, and then subjected to temperature cycling (−55°C to +125°C) with continuous monitoring of solder joint integrity. The total of 15 experimental cases is used in the present study. Based on monitored results, a destructive physical analysis is conducted to further isolate the failure locations and determine the failure mechanisms of the solder joints. Test results indicate that the influence of these design parameters on fatigue life is dependent on the particular package, in some instances improving the fatigue life tenfold.

With the development of artificial intelligence (AI) and high-performance computing (HPC) technology, advanced packages such as CoWoS (Chip on Wafer on Substrate) have become more popular in recent years due to its outstanding signal transmission speed and space management efficiency. Nevertheless, such high-power applications and the large size of heterogeneous integrated package may lead to thermal and high package warpage problems. In that case, the high stiffness heat spreader is usually used to solve the problem of large warpage. However, structural damage caused by stress and additional thermal resistance from the interface between heat spreader and die top surface have occurred. In terms of stress and thermal issues, optimizing packaging material selection and high thermal conductivity thermal interface material (TIM) are widely used to reduce the stress risk and enhance thermal performance. Therefore, it is important to accurately predict mechanical stress performance and thermal behavior. In this study, the thermal conductivity that considers real application of TIM needs to be extracted to ensure the FO-EB-T (Fan-Out Embedded Bridge with TSV) package thermal performance. In order to achieve this purpose, junction-to-case thermal resistance (ӨJC) measurement of large lidded FCBGA thermal test vehicle (TTV) is firstly measured to ensure the silicon based/graphite/alloy based TIMs thermal performance with liquid-cooling test fixture. Scanning acoustic tomography (SAT) and destructive physical analysis (DPA) are measured to check the TIM coverage and bond line thickness (BLT). Then, thermal conductivity which considers the interface effect is calculated by heat transfer equation using ӨJC, TIM coverage and BLT results. After extracting the thermal conductivity from the TTV measurement, a thermal simulation is constructed to ensure thermal behavior of the large lidded FO-EB-T test vehicle with the liquid cooling system using FloTHERM. Finally, the mechanical performance of the FO-EB-T is simulated by ANSYS to check the warpage and stress behavior. The structural material optimization is proposed to ensure the package warpage performance while reducing the chip module epoxy molding compounds (EMC) stress risk. Overall, the paper proposes a method that can extract the thermal conductivity of TIMs in real application. And further ensure not only the thermal performance but also mechanical behavior of large lidded FO-EB-T by thermal and mechanical simulation. Above that, the FO-EB-T package development that can save the design of experiments (DOE) and the thermal behavior consider real application are being proposed.